#356 – Tim Dodd: SpaceX, Starship, Rocket Engines, and Future of Space Travel

Tim Dodd is host of the Everyday Astronaut YouTube channel, where he teaches about rocket engines and all things space travel. Please support this podcast by checking out our sponsors: – BetterHelp: https://betterhelp.com/lex to get 10% off – MasterClass: https://masterclass.com/lex to get 15% off – Shopify: https://shopify.com/lex to get free trial – ExpressVPN: https://expressvpn.com/lexpod to get 3 months free EPISODE LINKS: Tim’s YouTube: https://youtube.com/@EverydayAstronaut Tim’s Twitter: https://twitter.com/Erdayastronaut Tim’s Instagram: https://instagram.com/everydayastronaut Tim’s Website: https://everydayastronaut.com PODCAST INFO: Podcast website: https://lexfridman.com/podcast Apple Podcasts: https://apple.co/2lwqZIr Spotify: https://spoti.fi/2nEwCF8 RSS: https://lexfridman.com/feed/podcast/ YouTube Full Episodes: https://youtube.com/lexfridman YouTube Clips: https://youtube.com/lexclips SUPPORT & CONNECT: – Check out the sponsors above, it’s the best way to support this podcast – Support on Patreon: https://www.patreon.com/lexfridman – Twitter: https://twitter.com/lexfridman – Instagram: https://www.instagram.com/lexfridman – LinkedIn: https://www.linkedin.com/in/lexfridman – Facebook: https://www.facebook.com/lexfridman – Medium: https://medium.com/@lexfridman OUTLINE: Here’s the timestamps for the episode. On some podcast players you should be able to click the timestamp to jump to that time. (00:00) – Introduction (06:18) – SpaceX rockets (26:56) – Falcon 9 (31:08) – Starship (35:27) – SpaceX rocket engines (43:05) – Elon Musk (58:41) – Twitter (1:04:46) – How rocket engines work (1:09:37) – Rocket fuel (1:13:03) – Rocket engine cycles (1:25:27) – Rocket cooling (1:40:24) – Multistage rockets (1:43:57) – Single-stage-to-orbit (1:49:33) – Aerospike engine (1:57:18) – Greatest car engine of all time (2:02:27) – Starship (2:05:19) – Wet dress rehearsal (2:11:29) – Landing (2:25:47) – Seeing starship in person (2:34:54) – Starship orbital test (2:41:32) – Gwynne Shotwell (2:46:43) – dearMoon project (3:05:46) – Fear of death (3:14:12) – Everyday Astronaut origin story (3:40:04) – Soviet Rocket Engine History (3:58:51) – Russia, China, USA (4:13:20) – Starlink (4:21:06) – First human on Mars (4:24:04) – Moon landing (4:30:11) – Nuclear propulsion (4:37:51) – Bob Lazar (4:44:54) – Aliens (4:48:42) – Sci-fi books (4:52:00) – Long-term space travel (4:58:47) – SpaceX competitors (5:10:07) – Kerbal Space Program (5:16:33) – Advice for young people

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Lex Fridman?

  The following is a conversation with Tim Dodd, host of the Everyday Astronaut YouTube channel, where he educates and inspires all of us with detailed but accessible explanations of rocket engines and all things space travel. And now, a quick few second mention of each sponsor. Check them out in the description. It's the best way to support this podcast. We've got BetterHelp for mental health, MasterClass for online learning, Shopify for e-commerce, and ExpressVPN for privacy and security. Choose wisely, my friends. Also, if you want to work with our team, we're always hiring. Go to lexfridman.com/hiring. And now, onto the full ad reads.

• 0:44Lex Fridman?

  As always, no ads in the middle. I try to make these interesting, but if you skip them, please still check out our sponsors. I enjoy their stuff. Maybe you will, too. This episode is brought to you by BetterHelp, spelled H-E-L-P, help. There's quite a few conversations coming up, including with Paul Conti, that really delve into the human mind, the complexities of the human mind formed through whatever happens to us when we're young, in our childhood, the difficult stuff, the good stuff, everything, the whole shebang. And some of that is trauma. And I think the shadow that trauma leaves in the human psyche is significant and deserves

• 1:29Lex Fridman?

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• 2:13Lex Fridman?

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• 2:18Lex Fridman?

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• 3:03Lex Fridman?

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• 3:32Lex Fridman?

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• 4:30Lex Fridman?

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• 5:53Lex Fridman?

  This is the Lex Freedom Podcast. To support it, please check out our sponsors in the description. And now, dear friends, here's Tim Dodd.

• 6:18Lex Fridman?

  Can you give a brief history of SpaceX rockets? So we got Falcon 1, Falcon 9. There's different versions of those Falcon Heavy, Starship, and also the Dragon capsules and so on.

• 6:29Speaker 01

  Well, yeah, Falcon 1 is where it all started. The original intent and the original idea of SpaceX was Elon wanted to try to get something to Mars. You know, he saw that NASA didn't have a current Mars plan. And he wanted to go to Mars. So he decided, how do I best do this? He literally wanted to at first purchase a rocket from Russia. Then on the, after a foiled attempt at doing that, he decided that he was going to try to develop his own rocket. And the Falcon one is what came out of that process and he developed a pretty incredible team. I don't know how exactly he stumbled upon the team that he stumbled upon that quickly. But the people that he assembled were amazing and they built the Falcon one,

• 7:11Speaker 01

  which was a single Merlin engine, followed by an upper stage engine called the Kestrel engine.

• 7:18Speaker 01

  Pretty small compared to the things they're working on today, but that Merlin engine continued to evolve into being the power plant for the Falcon nine. They went from a small lift launch vehicle up into the medium class launch vehicles. They could provide services for NASA.

• 7:32Speaker 01

  That's one of the big things they first kind of hung their hat up was they got the opportunity to fly cargo to the International Space Station. Under originally it's called the COTS program, the commercial orbital transportation services for NASA, which evolved into the commercial resupply contracts. And that's when SpaceX developed both their Dragon capsule, which is a uncrewed at first spacecraft that can dock to the ISS and the Falcon nine rocket that can take it to the International Space Station.

• 7:59Lex Fridman?

  The Dragon rides on, it's a thing up top that rides on the big booster thing that that launches it into orbit.

• 8:09Speaker 01

  Exactly. Yep. The Falcon nine is the semi truck. The Dragon capsule is the payload. You know, it's the thing being dropped off basically at a destination. And in this case, the destination is the International Space Station. And yeah, so they developed those relatively quickly and became a commercial success before you know it. They're now the number one launch provider in the world, launching more mass to orbit than anybody else, launching more frequently than countries, like the entire country of China who's going crazy right now with launches. Granted, China beat them by two launches this last in 2022, but. Prior year SpaceX beat the entire country of China. I mean, it's nuts.

• 8:51Lex Fridman?

  And just like you said, SpaceX still beats China even this year in terms of the amount of payload those.

• 8:59Speaker 01

  So.

• 9:00Lex Fridman?

  Yeah, the mass to orbit, right? That China had like 60 something, a couple more launches. But there was just like small cubes, that type of launches.

• 9:12Speaker 01

  Exactly. Some of them were literally like 100 kilograms or something, you know, like not, not large payloads.

• 9:17Lex Fridman?

  And so SpaceX customers are different and different. So whoever wants to send payloads up into space.

• 9:25Speaker 01

  Yes, but right now their biggest customer is actually themselves with Starlink.

• 9:29Lex Fridman?

  With Starlink.

• 9:30Speaker 01

  One of the biggest reasons they've launched so much mass to orbit is because Starlink is designed around the payload fairing and the payload capabilities of the Falcon 9 rocket. So, you know, because they're vertically integrated, because they build their own satellites, because they're building their own rocket. They can literally design a system that's, you know, another manufacturer might have made a more square satellite that was heavier or something. But SpaceX looked at it from a blank slate and said, here's our constraints, our payload mass constraints, our volume constraints. And they made a funky looking satellite, things like the size of a, you know, it's like a table folded up, which isn't anything I've, you know, really ever seen before. So, but it's purpose built to fit as efficiently as possible inside their fairing and inside the capabilities of that rocket.

• 10:10Speaker 01

  So therefore, because they're launching those like an insane amount, you know, a dozen, you know, 40, 50 times a year or whatever. They're, they're just putting up insane amounts of mass like we've never seen before.

• 10:23Lex Fridman?

  What about the different versions of Falcon 9? So we can linger on that. What are some interesting memories to you of the different developments in Falcon 9?

• 10:30Speaker 01

  The very first Falcon 9s had a square array of engines. It had like a three by three by three grid of their Merlin 1 engines, the 1Ds. And I think it only lasted, I don't remember if it was two or four flights before they went into this octo configuration where there's eight, like a ring of eight engines with a center engine in the middle. Still on the same diameter that the rocket was, the fuselage was more or less the same 3.7 meter wide diameter. But the, the actual thrust structure changed. And then one of the big efficiency gains was you no longer have, you know, a corner engine and then like a. Edge engine and then another corner engine. You can just make eight of the same, you know, kind of part of the octo web. It's called, you know, the same shape.

• 11:12Speaker 01

  And then your interchangeability and your manufacturability becomes a lot simpler. So that was kind of one of the bigger upgrades at first and they kept stretching it every time. They like touch this thing. It got longer and like taller and taller technically. And then the next big feature that you saw in 2014 would have been they added landing legs to a Falcon nine rocket, which is I was at, that was the first launch I ever went to was actually to see it was CRS three. So commercial resupply mission three. And it was probably their, God, I don't remember what that was like their 14th or 15th launch or something like pretty early on. And people were literally laughing at the idea of them putting landing legs on it. They just thought it was stupid. They're like, why are they wasting, why is this billionaire? Elon Musk guy wasting his time trying to land a rocket. It's not going to work.

• 11:57Lex Fridman?

  So you said the Mars planet was there in the beginning. What about the reusability of rockets? Was that there in the beginning?

• 12:05Speaker 01

  I think reusability definitely, you know, it's a necessary part of making any kind of interplanetary mission, you know, in order to actually do that, just financially, you have to start reusing these things.

• 12:18Lex Fridman?

  In terms of the development of the Falcon one and Falcon nine, how early on did the goal of reusing the rocket, having the rocket actually land? How early did that goal creep in?

• 12:32Speaker 01

  I can't speak for Elon and SpaceX, but it was pretty, you know, immediately they wanted to try to recover. And as a matter of fact, I think the very first two Falcon nine rockets and Falcon one, I think they even wanted to try to recover using parachutes to recover the first stage. And now fast forward, you know, almost 20 years later and Rocket Labs actually doing a concept like that where they're pulling a parachute after the first stage is reentering and they actually are trying to recover it with a helicopter. He's going to try to snatch it out of the air. They've actually done it. They've actually done it successfully once.

• 13:05Lex Fridman?

  How does the helicopter grab the rocket?

• 13:07Speaker 01

  With this giant like drag line and a hook.

• 13:09Lex Fridman?

  Oh.

• 13:10Speaker 01

  And then literally just like grab snags onto the parachute.

• 13:14Lex Fridman?

  Wow.

• 13:14Speaker 01

  It's pretty amazing. And but this is a small rocket. Their rocket's only about a metric ton. The booster is empty.

• 13:21Lex Fridman?

  So the rocket releases parachutes.

• 13:23Speaker 01

  Yep.

• 13:24Lex Fridman?

  Like really high up. I'd love to see this.

• 13:27Speaker 01

  Yeah.

• 13:27Lex Fridman?

  It's an interesting idea. There's so many interesting ideas and possibilities like SpaceX basically just innovated a lot of different weird ideas, just in the pursuit of making things more efficient, reusable. All of that. So basically thinking from first principles, how to solve this problem. And so what you find is like, you'll get all these kind of crazy kind of solutions.

• 13:48Speaker 01

  And with SpaceX, they weren't even getting to the point of the booster surviving reentry long enough to be able to pull the parachutes.

• 13:54Lex Fridman?

  Yeah.

• 13:54Speaker 01

  You know, their mass fractions, you know, and that varies. Every single rocket's different, you know, all the, you know, for instance, Rocket Lab uses carbon composite fuselage and tanks, or, you know, same thing. And that's very, very lightweight, has really good mass fractions, and therefore their drag coefficients and things like that. They were able to survive reentry of the first stage, which is something that SpaceX wasn't able to do at the time. What's what the kind of the big, I think, breakthrough for SpaceX with reusing the booster is they they realized we have to basically slow down before we hit the atmosphere. So they actually do what they used to call a reentry burn, which I still think is the correct term because it is reentering the atmosphere. But now they call it the entry burn. And they light up three of the nine Merlin engines,

• 14:39Speaker 01

  not only to slow it down, but actually even while those engines are firing, it creates like a literal like force field as it's falling through the through the atmosphere.

• 14:47Lex Fridman?

  Interesting.

• 14:48Speaker 01

  And but it also decreases the velocity by almost half or around half. And then that therefore decreases the amount of, you know, the biggest thing with the atmosphere is that as it gets compressed against the the front of any, anything flying through the atmosphere, the compressed atoms just get hot. And they can get so hot, they turn into a plasma and they get so hot, they can just absolutely destroy anything. So they slow down enough that the air molecules don't end up, you know, destroying the vehicle on reentry. And then they then they realized, I think at some point, there's probably a similar crossover. They're like, well, if we're lighting the engines already to slow down in the atmosphere, we can just use that same engine to land. And so like, well, what if we just stuck landing legs on it and just landed the thing vertically?

• 15:31Speaker 01

  And next thing you know is December 21st, 2015, they did exactly that for the first time.

• 15:36Lex Fridman?

  The first time. So you were there before that then, right?

• 15:39Speaker 01

  Yeah.

• 15:39Lex Fridman?

  In 2014?

• 15:40Speaker 01

  Yep, early 2014. So that, and for me, like, that was so fun watching, you know, that was like the peak of me just becoming obsessed with, uh, with this idea. I'm watching with, like, and back in the day, it was like months between launches, you know? So a launch was like a big idea. I'd wake up at 3 a.m. to watch this landing attempt or whatever, you know? And every, you know, there's CRS 4, um, almost, almost landed CRS 5, almost landed CRS 6, CRS 7 blew up. I was watching that on, I think it was like a Saturday morning or maybe a Sunday morning. And I remember watching that and watched it blow up and I was like, oh my God, now what? You know, and it blew up on ascent. It was their first failure. Um, so it was their 18th flight, I believe.

• 16:21Speaker 01

  CRS 7, the upper stage, um, had a, uh, one of the bottlers, bottles inside the tanks that are filled with helium. And one of those bottles broke off on ascent and actually just completely overpressured the, the upper stage. And the upper stage blew up and the whole rocket went kaboom, uh, in an uncontrolled manner. And so, uh, so then they came back with vengeance. And when they came back, the first mission back is the first time that they landed a rocket, which was awesome. So the return to flight after the anomaly was, was, uh, yeah, was, was landing a rocket.

• 16:50Lex Fridman?

  And stuck the landing.

• 16:51Speaker 01

  Yep.

• 16:52Lex Fridman?

  Well, actually the first time, so the first time you were there, what was that like? What do you remember from that, from that day?

• 16:57Speaker 01

  Just, I was surprised at how much bigger the rocket was than I imagined. I was, I originally, when I was going down to Kennedy Space Center, I was disappointed that I wasn't seeing like a, you know? I didn't know a ton about rockets. I knew enough to like know what a space shuttle was, what like the Saturn V was, you know? But that was probably about the end of my knowledge. I just remember being disappointed that I wasn't seeing a big quote unquote NASA rocket flying. You know, I was thinking in my head like, oh, I'm going to see this launch. It's probably going to be like, you know, three stories tall or something, you know? Just some little skinny little stick and. Some little firecracker and yay, you know, and I think I'd almost been pitched that too. I think the, the people that I was working for at the time, I think they kind of were downplaying it. It's like, well, it's not a big rocket here. It's not going to be that exciting, you know?

• 17:40Speaker 01

  But we get out there to the pad and I'm like, this thing's huge. This is not a small rocket. Like this is, it's, you know, it's 70 meters tall, 220 feet tall. It's huge. And I think people forget like the scale of that, you know? It might look skinny and tall and all this stuff, but it's still a very, very large piece of machinery. It's physically about as, as large as you can ship. The booster is about as big as you can ship across the country, period. Without like completely shutting down highways, you know? It is made within those exact specifications of, of like having, you know, lane privileges and bridges and everything. It's, you know, 12 feet wide, 3.7 meters wide, and it's 45 meters long. So it's like exactly what you can fit with a pretty standard, you know? Like before we start getting into crazy amounts of, of problems shipping the rocket.

• 18:26Speaker 01

  And it's huge. It's huge and people just don't understand that. And so when I saw it with my own eyes, I remember just being like, this is so much cooler than I thought.

• 18:33Lex Fridman?

  Is it hard to believe that that thing is going to have to lift off the ground and launch up into the air? Maybe that's the most humbling aspect of it. That's something that size. Humans have come up with a way to take something that size and launching, launch it up into the air.

• 18:48Speaker 01

  Yeah, there's certainly a very humbling aspect when you watch it actually leave.

• 18:52Lex Fridman?

  Was, was there a sound to it? Was there like a feel, what were the different experiences that you first remember?

• 18:57Speaker 01

  Well, ironically, I didn't end up getting to see that one fly. I went home, my camera saw it. I left my camera out there, like a remote triggered camera. My first images as a launch photographer at the time was, it was CRS 3, but I went home. It scrubbed too many times. Now, this is back in the day, they were scrubbing like often, and they'd be like a three day, five day, seven day. You just never knew. So I go home and I watched the live stream of it. So I didn't even get to experience my first launch. And any, anyone that's ever tried to, you know, go to a launch is, can probably empathize because yeah, scrubs are very common in the spaceflight world. So that one I didn't get to see, but since then, obviously I've been able to attend very many launches.

• 19:36Lex Fridman?

  How much do you understand the control involved in the landing? How difficult is that problem?

• 19:40Speaker 01

  I couldn't tell you a single thing about like the code and like the avionics behind it, but I can tell you all the hardware that makes it happen. If that helps.

• 19:47Lex Fridman?

  Well, that, I mean, to me, it seems like whenever I talk to people, they, they say it's not that big of a deal in terms of the, the level of intelligence in the control. But to me, it's just like when you observe it. It seems incredible because all the variables involved, all the uncertainties involved, all the because there's aerodynamics, like there's different temperatures, there's so much going on with the fuel, the burning, the combustion, just everything that's going on to be able to do, perform control at such high stakes effectively, like, you know, that code is probably not written in JavaScript, I guess is what I'm saying.

• 20:25Speaker 01

  Actually, no, I don't, if I remember, again, this is well outside my domain, but they're coding in a common language, it's

• 20:36Lex Fridman?

  It's probably going to be C.

• 20:38Speaker 01

  Yeah, I'm pretty sure it is. And that was one of the things that was weird is that Elon, when he, you know, started SpaceX, like, we're just going to code in the most common language so that we don't have to like, have people learn this archaic, you know, weird thing, and we can just literally pull people off the streets and be like, here, write it, you know, and

• 20:53Lex Fridman?

  Yeah, it's probably C++ I mean, it'd be epic if it was like Python or something, but I don't, I think, like, reliable systems have to be written in C, C++ probably, which is a common language, which is something, I imagine, like, NASA engineers would probably have to use some kind of proprietary language in the olden days for, for security, for privacy, all that kind of stuff.

• 21:13Speaker 01

  And the old, old, old days, like, they were inventing code and language from scratch.

• 21:20Lex Fridman?

  It's still, it's just still incredible that it's able to do that, like, just the feat of engineering involved is just, it's truly, it's like, one of the marvels to observe about these rockets coming back to Earth, that they're able to land, like, the drama of it is just incredible to see.

• 21:38Speaker 01

  Yeah, well, the, one of the fun things to remember, too, with, specifically with the Falcon 9 and the Falcon 9, or Falcon Heavy boosters, I mean, it's the same thing, basically, they shut down all but one of the nine engines. And even with that one engine at its minimum throttle setting, it's still too much thrust to hover. So as this rocket's coming down, if they start a little bit too early, if they light that engine too early, it will actually stop above the ground and will not be able to lower itself. It will literally stop, like, say, say it's stopped 200 feet above the ground. Their only option is to kill the engine and then it's just going to fall those 200 feet. So they, it's what we call like a suicide burner, a hover slam, kind of interchangeable terms. Because your thrust to weight ratio is never below one.

• 22:22Speaker 01

  So they have to actually literally be riding the throttle. So what you do is you kind of start, ideally, you know, you kind of start like in the middle of your window of, of throttle range. So let's pretend your engine can throttle down to 40% of its maximum rated thrust. You might start at like 70% of thrust in the middle of that like window of where it could burn. So that, so if all of a sudden it's kind of coming in too hot, you have room to throttle up. If you're coming into, you're actually, you know, a little too early, you throttle it down. You have a little bit of wiggle room. It's just amazing how smoothly and how perfectly they're able to still control that thing. Even though they're down to one engine out of the nine and they're still riding like the finest margin of what's possible. And they're, they're continually playing with that to try to get it.

• 23:00Speaker 01

  Cause every, every bit of fuel they're using and propellant they're using to land is propellant they weren't using to put something into space.

• 23:08Lex Fridman?

  Yeah.

• 23:08Speaker 01

  So they want that to be as efficient as possible. So they're really like watching them hone that in and, and just continue to evolve and edit that and just get it to be the workhorse. We're coming up on a hundred consecutive landings. Perfect landings, a hundred. I think they've done like a hundred and 50 something landings altogether, a hundred and 60 altogether. But we're talking like in a row without blowing up, which at the, you know, five years ago was completely experimental and insane. And now we're coming up to the point where we're a hundred in a row. It's like, this is becoming more reliable in the landing, which is not the primary mission. This is purely for SpaceX's like gain is to recover the booster. It has nothing to do with the effect of getting the payload on orbit, you know, most of the time. And the landing is really only for their, their benefit and their gain.

• 23:53Lex Fridman?

  Long-term gain, like it's a long-term investment in, in being able to recover the, the boosters.

• 23:59Speaker 01

  A hundred.

• 23:59Lex Fridman?

  Can you believe all this was done in basically 10 years? So that we've seen this development over a period of 10 years.

• 24:05Speaker 01

  Oh man.

• 24:06Lex Fridman?

  So like where we started, uh, commercial spaceflight.

• 24:11Lex Fridman?

  At scale to today, where it's almost, almost starting to be mundane.

• 24:17Speaker 01

  Yeah.

• 24:17Lex Fridman?

  Fucking nice to do.

• 24:19Speaker 01

  Yeah, I can't really believe it. I mean, obviously, even just in the, I think I'm a fairly fair weather fan, really didn't start paying attention to like 2014.

• 24:28Lex Fridman?

  Yeah.

• 24:28Speaker 01

  And just seeing what it was like back then to what it's like, like, I don't watch every launch at all anymore. Like, I'll catch the big ones. I'll stream some of the really big ones, but like back in the day, I, like I said, would wake up in the middle of the night to catch these streams or, you know, catch these launches and watch them because they were such a big deal. And there's maybe only five of them a year, you know? And so it's a really big deal. Nowadays, it's like, oh, yeah, and there's literally like two a week on average now. It's insane from SpaceX alone, let alone, you know, United Launch Alliance, Rocket Lab, any of the Chinese missions, you know? I mean, all of, there's countless, it's insane. It's hard to, really, really, really hard to keep up with.

• 25:04Lex Fridman?

  I wonder at which point in the future, the number of launches to orbit will exceed the number of launches of airplanes, like on the surface of Earth.

• 25:15Speaker 01

  Yeah, I have to admit, I kind of have a hard time extrapolating out that far. You know, there's a lot of people that are like big futurists and really do think about like interplanetary stuff and think about colonizing Mars and stuff. I have a hard time predicting like when Starship's gonna fly, the orbital launch, you know? And that's like imminent-ish, like month or two scale timeframe. And yet I'm still like, I can't tell you when that's gonna, I can't tell you anything about like when we're gonna land on Mars or what that's, what that economy and what that, you know, the scale of launch operations is gonna look like in order to do that. Because it's just so hard to, I wouldn't have predicted where we're at today, five years ago, you know? It's, it's insane. It's so hard to predict and, yeah. But it's funny because there's so many like new companies starting up trying to predict that. And it's a really exciting, you know, startup culture.

• 26:01Lex Fridman?

  I think when you make certain engineering decisions. And hiring decisions and like what you focus on in terms of both business and engineering. It's good to think on a scale of 10, 20, 50, 100 years. That's one of the things that Elon is exceptionally good at, which is asking the question, okay, this might seem impossible right now, but what's the obvious way to do this if we look out 20 years? And then you start to make decisions. You start to make decisions about robotics, about brain and computer interfaces, about space travel. They're, they make a lot of sense when you look at the scale of 10, 20, 15, 100 years and don't make any sense if you, if you look at

• 26:40Lex Fridman?

  the scale of just months. So, but of course, the actual work of day to day is focused on the next few months because there's deadlines, there's missions they have to accomplish. Anyway, we are returning back to the brief history.

• 26:56Lex Fridman?

  The Falcon Heavy. So what else is there? So we talked about Falcon 9 and the rapid development there. What other flavors of Falcon is there and how does that take us to Starship?

• 27:06Speaker 01

  Yeah. Realistically, the Falcon 9 evolved more or less kind of like just got more powerful and a little bit longer and more capable. But nowadays they fly what's called the Block 5, even though it's like the eighth or ninth iteration of the Falcon 9, but they call it Block 5. It's the one that has the black landing legs, the black inner stage. They have a fleet of roughly 10 or so that are doing the majority of the legwork these days and they're flying, you know, up to 15 times, I think, right now as the current booster leader. They're also recovering the fairings. So the nose cone of the rockets are frequently, if not every time, being recovered. Same with the, same with the booster for the most part. And the only thing being expended is the upper stage and that's kind of where the Falcon 9 is ending.

• 27:48Speaker 01

  It's really doesn't make sense to develop that infrastructure any longer. So they went with the next step, which is go even bigger. Physically, so they have more margin for upper stage reusability. And that's what we see with Starship and Superheavy. So the Superheavy booster, the whole system is confusing. The whole system is kind of considered Starship. But technically, the Starship is just the upper stage, which is also like the spaceship, which is also the upper stage. And then the booster itself is considered the Superheavy booster. And that's what they've been working on. Publicly, it came out in 2016 as the, at the time it was the ITS, the Inter Planetary Transportation System. Later, and I think about 20, by the end of that year, 2017,

• 28:32Speaker 01

  it kind of became known as the BFR, the big Falcon rocket.

• 28:36Lex Fridman?

  Yes.

• 28:36Speaker 01

  Yeah. And then I think it was about end of 2018, they started calling it Starship. But that is the, that is where we're at today. And that's what they're working full steam ahead on.

• 28:47Lex Fridman?

  And what about Dragon? We mentioned Dragon, Crew Dragon, Cargo Dragon.

• 28:51Speaker 01

  Yeah. So they went from the cargo version of Dragon that flew about 20 times successfully to the International Space Station, except for that one CRS-7 where the rocket blew up in the capsule. Obviously, it didn't make it to the ISS. Then they went into the Dragon 2, which has two variants. It has a crew variant, so we just call it Crew Dragon. And then there's the cargo version of Dragon 2. And that's just an updated, sleeker, sexier version of Dragon. And it's ironically, it's heavier altogether. So you'll never see those, those cool return to launch site landing, the boosters coming back to land for CRS missions anymore like we used to. But they landed on the drone ship anyway. And, and yeah, that's been flying successfully.

• 29:35Speaker 01

  That's kind of the, so there's Starlink, Dragon, Falcon 9, Falcon Heavy and Starship system. It's kind of the whole, the whole SpaceX world, really.

• 29:42Lex Fridman?

  In terms of the, the spaceships involved. So what do you, are some of the major milestones in that history? We kind of mentioned the A few.

• 29:51Speaker 01

  Yeah.

• 29:52Lex Fridman?

  Sticking the landing. Is there something that kind of stands out?

• 29:54Speaker 01

  Yeah, I would say definitely the big ones, obviously, like any of the first, like the first flight of Falcon 1, first flight of Falcon 9, first time they went to the International Space Station. The first time they landed a booster, the first time they reused a booster, which is, I think, about six months after. No, it was a year after. It was SES 10. 2017. It was the first time they reused one of those boosters, you know, and that was a big milestone. Like, can we even? Yeah, we recovered one. We caught one, you know, it's like, we got one, now what? That was the first time they reflew one. Yeah, then flying humans was a huge one, DM2, Bob and Doug for NASA.

• 30:31Lex Fridman?

  Bob and Doug, yeah.

• 30:33Speaker 01

  That was incredible, you know, that was, that was a huge, huge step, I think, for SpaceX was flying people.

• 30:39Lex Fridman?

  So it's first major commercial launching of humans out into space.

• 30:44Speaker 01

  Yeah, and not just into space, because, you know, there's been people that have done, you know, space flights with, you know, like suborbital hops, but going into orbit. And especially docking and rendezvous with the International Space Station is a, it's a big deal. It's a whole. It, until you really understand the physics involved and the scale involved of like just crossing the Karman line, going straight up versus going into orbit, like they're just completely different things almost.

• 31:08Lex Fridman?

  What about Starship?

• 31:11Lex Fridman?

  Are we in a place where we can talk about milestones with Starship? Has there been, or has it just been an epic journey of failure and successes of testing and so on? Was there like, yeah, what would you classify at this point as a, as a milestone, a Starship or BFR, whatever the name is, was able to achieve?

• 31:31Speaker 01

  Well, so far the milestones we've seen, I'd say the first one would be the hop of, they call it Starhopper, and it's basically a very rudimentary rocket, but it was the first time they, they utilized their new Raptor engine to produce thrust to fly something. It first flew like, literally like, three meters off the ground or something like tethered to the ground, then it flew like 15, and then finally it flew 150 meters. And that was in 2019. And that was the first big milestone of Starship. And then after that, we saw SN5, SN6 kind of do the similar like 150 meter hops with a little bit more elegant systems, you know, proving out more of their, their tank building, proving out more of their, you know, a lot of just subsystems.

• 32:11Speaker 01

  And then the big ones physically were in, and end of 2020 and early 2021 when they flew the SN8, 9, 10, 11, and 15.

• 32:20Lex Fridman?

  What does the N stand for in SN?

• 32:22Speaker 01

  I think just serial number or starship number.

• 32:24Lex Fridman?

  Yeah, so SN, these are just names, numbers, numerical representations of the different testing efforts. They skip some numbers, right?

• 32:32Speaker 01

  Yeah.

• 32:33Lex Fridman?

  If they, if they scratch a test.

• 32:35Speaker 01

  Yeah, and lots of times it'd be like literally they're building, you know, because at Starbase and what SpaceX is working on, like the one foot is always in front of someone else's foot and like the arm is not knowing what the leg is doing sometimes.

• 32:45Lex Fridman?

  Yeah.

• 32:47Speaker 01

  They, they will have someone working on, you know, they'll just be like, hurry up and build 40 of these tank sections and you build the bulkhead and you build the downcomer and you build the header tank, blah, blah, blah. And all of a sudden like, oh, we actually evolved that. We don't use that header tank now. So it's going to go on to this one. So they'll have like parts of certain rockets built and it's like, ask, literally scrap it, like not scrap it like in the, you know, joke term, but like literally just go scrap it. And they, so they, yeah, they, they just evolve and iterate so quickly.

• 33:13Lex Fridman?

  There were some epic explosions. I think Starship, something about it, probably just the amount of fuel just leads to some epic, epic failures.

• 33:24Speaker 01

  Oh, yeah.

• 33:25Lex Fridman?

  Would you say Starship is the source of the most epic failures in terms of size of explosion?

• 33:30Speaker 01

  So you can literally measure in like a yield of explosive power, you know, like, like you could TNT. Like you can take a look at how much propellant is left over at the, at the time of the explosion. And, and you know, Starship, what's flown so far, even though it's physically one of the largest flying objects ever, just with the upper stage alone, they've not filled it more than like 10 or 20% full of propellant.

• 33:51Lex Fridman?

  Yeah.

• 33:52Speaker 01

  And so it actually hasn't been, the, the failures have been really epic looking, big visual fireballs, but in terms of spaceflight, they're still pretty small explosions, believe it or not.

• 34:04Lex Fridman?

  They could still go bigger.

• 34:05Speaker 01

  Oh, yeah. A lot, a lot.

• 34:07Lex Fridman?

  And of course. The test payload of a Tesla Roadster was launched. I forget what year that was.

• 34:13Speaker 01

  Yeah, that was 2018.

• 34:14Lex Fridman?

  That was quite epic. Would you put that on a milestone?

• 34:17Speaker 01

  Oh, yeah. Falcon Heavy Demo was like definitely a big, big, big milestone. Yeah.

• 34:23Lex Fridman?

  Is that funny to you that there's a Roadster floating out there?

• 34:27Speaker 01

  Yeah.

• 34:27Lex Fridman?

  Do we know the location of that Roadster at this?

• 34:29Speaker 01

  Oh, yeah. Where is roadster.com?

• 34:31Lex Fridman?

  Yeah?

• 34:31Speaker 01

  Oh, yeah.

• 34:32Lex Fridman?

  Where's, is it orbiting something?

• 34:33Speaker 01

  Yeah, it's orbiting the sun. So it's orbiting the sun and its orbit is basically between the Earth's orbit and beyond Mars. So I think of like 2.5 AU, if I remember right. So it's, it's beyond Mars's orbit at its highest point and it's back at Earth, kind of in its lowest point.

• 34:49Lex Fridman?

  I wonder if there's a mission where you're going to somehow connect with it once again and like place extra things into it. I wonder how challenging that is technically.

• 34:58Speaker 01

  Oh, yeah. It could, it could absolutely be done. You know, the, the hard thing at this point, because it's on an eccentric orbit, would be rendezvousing with it because you kind of had to be in alignment with its orbit to really line up well with it.

• 35:10Lex Fridman?

  Yeah.

• 35:11Speaker 01

  But yeah, I mean, someday I don't see any reason why we couldn't at least send for sure an uncrewed, you know, if Elon wanted to just fly a, a robot out there to check up on it and photograph it or something like we could, that could be well within the realm of things.

• 35:23Lex Fridman?

  Get an Optimus robot up there. So that was the story brilliantly told by you of the rockets for SpaceX. What about through the lens of engines? Can you give a brief history of the SpaceX rocket engines that were used that we haven't covered? You mentioned it all started with the Merlin engine and a Kestrel engine. What, yeah, through that lens?

• 35:48Speaker 01

  Yeah.

• 35:48Lex Fridman?

  What's there?

• 35:49Speaker 01

  Engines are relatively small number, which is, which is easy for us. There's the other Merlin and Merlin's evolved throughout time to be, from like the Merlin to the Merlin one C to the Merlin one D to the Merlin one D full thrust and all these other kind of tweaks of the same architecture. Kestrel ended with Falcon one. They also have the Merlin vacuum engine, which is the upper stage engine for Falcon nine. Same relative system, but just optimized for vacuum. So it has a much larger bell nozzle. There's the Draco thrusters, which, you know, you kind of can consider engines. Are rocket engines, but they're just small. They're not like the orbital engines. There's the super Draco engines, which are the abort thrusters on on Crew Dragon capsule. And then nowadays they have the Raptor engine and the Raptor vacuum variant.

• 36:34Speaker 01

  But they've already had two versions of Raptor. We've already seen kind of the Raptor development engine. We've kind of seen like a Raptor 1.5, whereas kind of taking hints of the future Raptor. But now we're well within the well within what you'd consider a Raptor two variant. And that's really it.

• 36:49Lex Fridman?

  Yeah, for the Raptor, maybe I'll ask you that separately, but I like in general. And people, who doesn't know whoever the astronaut is, but if you don't somehow know, go, go, go check his. Your YouTube channel out. You're an incredible educator about the the super technical and the more sort of even the the philosophical, the actual like the the actual space travel. So you go down to the raw details of it and there's just great videos on the Raptor engine.

• 37:20Lex Fridman?

  I think you have one on Merlin and and also the actual tours with Elon where he discusses some of those things. On one of the tours, he says, he's full of good lines, that guy. He says something about the number of fiddly bits. And he's, the number of fiddly bits was decreased between Raptor two and Raptor one.

• 37:42Speaker 01

  Yeah.

• 37:42Lex Fridman?

  And I think that's actually a really beautiful representation of the engineering efforts there, which is constantly trying to simplify. Increase the efficiency of the engines, but also

• 37:54Lex Fridman?

  simplify the design so you can manufacture it. And in general, simplification leads to better performance and testing and everything. So the number of fiddly bits, I'm sure there's a Wikipedia page on that now as an index is actually a really good one.

• 38:09Speaker 01

  Well, and when you think about it, I don't know of any other company prior that had kind of tried to measure their performance of their engine, not in like thrust to weight ratio or like how efficient it is like in specific impulse. But literally in like dollar to thrust ratio, like how much does this engine cost? How much thrust can it produce? And like using that as a trade study instead of just like pure metrics of, you know, because at the end of the day, like, okay, if it's if it's cheaper and does, you know, X amount of work, even if it's less efficient, it can actually be better long term.

• 38:39Lex Fridman?

  And so I guess another way it's not even just thrust. I don't know if that metric is used, but basically the cost of getting one kilogram. A thing up into space.

• 38:49Speaker 01

  Yeah.

• 38:49Lex Fridman?

  That's basically what they're trying to minimize.

• 38:51Speaker 01

  Especially, yeah. At the, at the end of the day, that is definitely the ultimate metric is how much does one kilogram cost to orbit eventually, you know, and but there's, it's so funny because spaceflight is just the ultimate, you know, it's the ultimate compromise. Every little thing, any variable can just change everything else. So you can tweak so many different things to get to different numbers and conclusions, you know, but even things like on your first stage, when you're, when you're, the rocket's pointing straight up and the engines are pointing straight down, you're dealing more with the thrust to weight ratio of the rocket. So how much thrust is it producing versus how much is gravity pulling down on it is actually a more important metric than how raw efficient the engine is. So it's funny, then in space, it's kind of the opposite thrust to weight ratio doesn't really matter.

• 39:35Speaker 01

  What really matters is the actual, the specific impulse, it's called, or like the nozzle escape velocity of the, or the injection velocity of the, how fast is the, the gas moving is like the more important number on orbit, but it's, it's just so crazy because there's all these, like, I would just love to see the trade studies, you know, when you're like trying to figure out like, is this more important than this or this or this? And it's like, you change this one little thing and all of a sudden, you know, like all the, everything changes. It's just even the profile, like the, the launch profile, the trajectory of it, the, I mean, everything, everything.

• 40:07Lex Fridman?

  I wonder what that trade out discussions are like, because you can't really perfectly plan everything. So, and you always have to have some spare leeway on, on, you know, especially as you're testing new vehicles like Starship.

• 40:22Speaker 01

  Yeah. So margins are important.

• 40:24Lex Fridman?

  Yeah, having, having a margin, given all the uncertainty that's there. That's really interesting, like how they do those kinds of trade outs, because they're also rapidly designing and redesigning and re-engineering. And the, ultimately, you want to give yourself the freedom to constantly innovate, but then through the process of testing, you solidify the thing that can be relied upon, especially if it's a crude mission.

• 40:47Speaker 01

  Yeah.

• 40:47Lex Fridman?

  That, how to do that in a rapid cycle.

• 40:50Speaker 01

  I remember at some point. That NASA, as they're leading up to flying humans for the first time for NASA, you know, there's some talk that like, we're going to do a design freeze because SpaceX does evolve and iterate so quickly. You know, they were saying that it was leading, because especially at the time, it was a mission called Amos 6. And they lost a rocket. They've only lost two rockets, like ever, really, as far as, um, you know, trying to get something to space, uh, for the Falcon 9, sorry.

• 41:18Speaker 01

  And the second one, Amos 6, I mean, that was back in 2016. So it's, it's been a long time. And, uh, but at the time, you know, they're looking at flying humans in the near future. And it's like, if you guys keep tweaking this thing every time you take it out to the pad, well, there's going to be a problem, you know? And so there is some pressure from NASA to kind of slow down on that iterative process. And, uh, but that is also why they were able to evolve the Falcon 9 to be what it is today is because they did just evolve it so quickly, literally like one after another was never really the same. And we're definitely seeing that with Starship now, like it's evolved so quickly that you just can't even keep up with it, you know?

• 41:58Lex Fridman?

  So there's a fascinating culture clash there. Have you just in observing and interacting with NASA folks, seen them sort of grow and change and evolve themselves, sort of inspired by this new developments in commercial spaceflight?

• 42:11Speaker 01

  Oh, yeah, yeah. There's a lot of, especially like around DM2, there's a lot of talks and the press conferences and stuff where you'd hear people say, you know, this was a big, this is well outside of our comfort zone to work with SpaceX in this manner, because we're, we take this approach to things. We're X, Y, and Z in this, in this way, the way we normally certify things. And we're not used to SpaceX like, well, let's just try it, you know, like, and, and do something, you know, to a point. And so they, they said it ended up being fantastic. They loved working that way because it was just less paperwork almost and more just do. And, um, and, but at the same time, SpaceX, I think even expressed, I don't remember if it was Hans Koenigmann or someone in a press conference said, well, we really liked having someone just double check us so that we're not doing something super stupid right before we test something, you know?

• 42:57Speaker 01

  Um, so there was a cool collaboration because it is, uh, two very different philosophies of, uh, of development and managing, you know, space programs.

• 43:05Lex Fridman?

  I wanted to talk to you a lot about engines. And maybe about Starship and maybe about your own becoming an actual astronaut. But like, let's just go there before all that and talk about the actual culture of SpaceX and your conversations with Elon. You've toured SpaceX facilities with him. You've interviewed him. You've interacted with him. What have you learned about rockets, about propulsion, about engineering, about design, about life from those interactions? He's pretty transparent, open human being as an engineer, as a leader, as a person.

• 43:44Speaker 01

  I would definitely say the biggest takeaway I've had from my times with Elon at SpaceX is really like the idea of question your constraints. He says that a lot, but he also does it a lot. Though, you know, there'll be times where like, you'll see him change on a dime because he's like rethinking of something in a newer, different way. And for me, you know, I think we all put constraints on ourselves. We think about our own limits, you know, on, on things that we can or cannot do. And I think it's made me kind of question like, well, why am I, why did I say, no, I can't do that? Or, you know, you know, just off the top of my head.

• 44:25Speaker 01

  A good example, I, so in Iowa, I live in Iowa, or half the time or whatever. There's a bike ride across the state of Iowa called Ragbray. And every year you just, you know, like thousands of people get together and they ride across Iowa. And it was last summer, I met up with some friends and like, hey, do you want to go on Ragbray this year? I'm like, it's like a week away. They're like, yeah, you want to go? I'm like, yeah. And so I did without, and it was one of those moments where I was proud of myself because it's like, I, it's easy to just be like, no, you know, I'm not ready or this is my constraint is like, I'm not in shape. But like, just question that, you know? And, and so I think when it comes down to questioning your own constraints, it's yes. Even to that level of like, why do you question yourself on what you can and cannot do?

• 45:07Lex Fridman?

  So that's for your personal life is really powerful, but a little bit more intuitive. I think what's really hard is to question constraints in a place like aeronautics or, or robotics, or autonomous vehicles, or vehicles. Because there's people, there's experts everywhere that have done it for decades. And everyone admires those experts and respects those experts. And you've, for you to step into a room, knowing not much more than just what's in a Wikipedia article.

• 45:39Speaker 01

  Yeah.

• 45:40Lex Fridman?

  And to just use your intuition and first principles thinking to disagree with the experts. That takes, that takes some guts, I think.

• 45:49Speaker 01

  Well, you can't have everyone doing that either, you know? Like, there has to be some humility of knowing that something is a hardened concept and a hardened, you know, like especially, I'm not an engineer. I don't, I don't do this stuff, you know? But I can imagine you sitting there, having spent six years on a type of valve that perfectly manages crouching propellants or whatever, and someone walks in and says, why don't you just put a heater element in there? You know, or something that's, you know, something like, because, you know, we've done that 40 times, whatever, whatever. You know, like, I'm sure there are things like that, that are very frustrating, but.

• 46:22Lex Fridman?

  But see, the thing is.

• 46:22Speaker 01

  I don't know what that's like, you know?

• 46:24Lex Fridman?

  The thing is, with the experts, they're always going to be frustrated when the newbie comes in with their first principles thinking. But sometimes that frustration is justified, and sometimes it's not. Sometimes it's just stubbornness for failing to acknowledge a better way. And I've seen it both directions, which is really interesting. So you need, you need both, but that tension is always going to be there. And there has to be a, almost like a dictatorial imperative that breaks through the, the expertise of the way things have been done in the past to push forward, like a new way of doing it. And Elon's done that. I've seen a lot of great engineers do that in the machine, the machine learning world. Because there's been so much development, I've seen that happen.

• 47:07Lex Fridman?

  Usually when there's like rapid development that starts to come into play.

• 47:11Speaker 01

  Yeah.

• 47:12Lex Fridman?

  And, yeah, and I've seen that autonomous vehicle space, brain computer interfaces that Elon has evolved with, all of it. It's kind of fascinating to watch. What about the actual design and engineering of the engine? Since you've learned. About so many different kinds of engines over the past few years. Just like what stands out to you about the way that engineering is done at SpaceX? Or that Elon does engineering?

• 47:38Speaker 01

  The hardest thing to kind of remember is like how much stuff was developed in the 50s and 60s. You know, the concepts finally being utilized today were already literally done in the 60s.

• 47:51Lex Fridman?

  Yeah.

• 47:51Speaker 01

  You know, so a lot of the things that SpaceX is doing isn't a novel concept per se. You know, they're like, for instance, the Raptor engine utilizes the full flow stage combustion cycle engine. And that was already developed by the Soviets in the 60s for an engine called the RD 270. And it's makes sense, like on paper, 100% it makes sense because you're basically extracting the absolute maximum potential of the chemical energy in both propellants. And, you know, at the, at the end of the day, like you had to be dumb enough to say, we're going to try using this thing because it's actually really complicated to, to do what they're doing. But at the same time, like so are, so are rockets, like rocket engines are already stupid complicated.

• 48:34Speaker 01

  So adding, you know, 10, 20% more, you know, pain in the butt during the R and D. If it's, you know, in the long, long, long 20, 30 year existence or whatever, you know, like future of that engine. Is that going to be worth it? Obviously SpaceX said, yeah, I think we can actually develop this, this Raptor engine. So it's, it's just interesting to see the things that have been looked at or even reusability. You know, like the space shuttle was reusable. It was fully the upper stage, you know, the shuttle itself, the orbiter was, you know, I mean, that thing was for all intents and purposes, a reusable rocket. Now, did it live up to its expectations? Not necessarily. So it left a lot of bad taste in people's mouth on the, the ideas of reusability.

• 49:17Speaker 01

  So for SpaceX to kind of come back into the room and on the table and say, we're going to use a reusable rocket. Specifically, we're going to do a fully reusable rocket. You know, a lot of people are, even still today, a lot of people going, yeah, you're not going to be able to do that.

• 49:29Lex Fridman?

  Even today?

• 49:30Speaker 01

  Even today?

• 49:31Lex Fridman?

  So like long term, you're not going to be able to reuse at scale.

• 49:36Speaker 01

  Yeah, but definitely, I think the number of people that are saying that today is is a small portion of those that were saying that type of thing five years ago. You know, when Elon did that announcement in 2016 for the I T S, it was very, very aspirational. And people were just like, yeah, right. You know, and there's a large number of people that had the factual reasons to think that and do that. You know, at the time, they'd only landed like two rockets or something, you know, when they did that, or maybe three. It was a very small number. When they announced that, actually, they had just lost a couple of months prior, they just lost M O six. So they like, they were still this young blossoming company. And to come in and be like, we figured out reusability, and now we're going to go full scale, make the world's biggest, most heaviest, most powerful rocket ever, and we're

• 50:20Speaker 01

  going to fully reuse it. And it's going to go to Mars. It was just pretty out there. Like, it really was. And, you know, it's all about perspective. But now, again, we're coming up on 100 consecutive landings of an orbital class rocket that's, you know, 45 meters tall, 3.7 meters wide. Like, this thing is huge. Weighs 20 metric tons even empty when it's landing. That thing's already huge. So seeing the success of that, I think people are now more like, well, okay, maybe, maybe there is actually the opportunity to be fully reusable. That's definitely probably the biggest constraint that I think has been questioned. That is.

• 50:55Lex Fridman?

  Reusability.

• 50:56Speaker 01

  Yep.

• 50:56Lex Fridman?

  And then, of course, like, the broader one of costs, of bringing down costs, that you're able to, you're able to kind of bring down costs so much that this, something like colonizing Mars, or many trips to Mars will be a possibility. People don't even, it seems so far out, that they don't even have time or give effort to questioning it. But it's the implied questioning. Can you really do that many launches?

• 51:23Speaker 01

  Actually do it.

• 51:24Lex Fridman?

  Can you actually do it?

• 51:25Speaker 01

  Yeah. It's looking, I think it's one of those things where you look at the curve. You know, you look at like, 10 years ago, that was ridiculous. Following this curve, if SpaceX goes from, you know, two years ago, launching, I don't remember what it was, 40 times to 60 times to 100 times this year, is there, is there amount? And if we just keep extrapolating that out, if they, maybe not that exponential, maybe it goes more linear, or whatever. What's 20, 30 years, like the amount of stuff we can put on orbit and the potential we have to do things like absolutely. Now, I don't want to put a timeframe like, you know, yeah, I think, but you got to think it's we're increasing the number of launches. We're increasing the amount of things in space. We're increasing the amount of payload on orbit. That's probably not going to decrease anytime soon. And therefore, eventually,

• 52:10Speaker 01

  like the idea of going to Mars is absolutely reasonable.

• 52:13Lex Fridman?

  Let me ask a difficult question that needs to be asked here. Can SpaceX continue its successes without Elon? This long-term mission to Mars. I think the discussion about Tesla and autopilot or robotics or neural link with brain computer interfaces is a question wholly separate from the SpaceX question. Because there's a lot of other competitors doing some different but amazing engineering that Tesla is doing in both autonomous vehicles, semi autonomy or full autonomy, and obviously in vehicle design,

• 52:56Lex Fridman?

  electric vehicles. There's a lot of people that are doing incredible brain computer interfaces. But while there is a lot of competitors to SpaceX, and we'll talk about many of them, they're doing amazing work. It seems like he's really driving progress here over the past 10 years. What do you think about that?

• 53:13Speaker 01

  Okay. The first thing I think to remind people is just how many brilliant people do work at each of these companies, obviously. You know, Elon's had the, some of the best teams assembled ever, just incredible people. He knows this. He will gladly tell people, and he says it often, like, the amazing people, the amazing teams here. So it is important to remember that. That being said, like, there is something to Elon's

• 53:39Speaker 01

  Just super far forward, not taking no for an answer on things approach that and and almost to his dismay, I think he is afraid of the sunk cost fallacy so much that it almost almost gets to the border of like being, you know, like throw out everything before it's even we've known or not. But at the same time, like it moves the needle so fast, so far. So as far as the question of would SpaceX continue to like succeeding and be able to ultimately go to Mars without Elon, the Mars thing I think would probably be hard to uphold without it. I think a lot of that drive for Mars is from Elon. It is maybe too fantastical for the average

• 54:21Speaker 01

  person and the average employee and maybe the average CEO that might step in to have a company's mission be to go to Mars. Like it's just-

• 54:28Lex Fridman?

  Or even governments, clearly, because like you said, the Mars plan was non-existent for NASA.

• 54:34Speaker 01

  Yeah, still really, there isn't much, you know. So I think if-

• 54:40Lex Fridman?

  How many people, and sorry to interrupt, how many people are talking about it's obvious that we need to become multi-planetary?

• 54:46Speaker 01

  Right. There's not, there's the Mars Society and-

• 54:50Lex Fridman?

  Like serious leaders of engineering efforts or nations and so on.

• 54:56Speaker 01

  Yeah.

• 54:57Lex Fridman?

  Which it does seem, if you think about it, that it's obvious.

• 55:01Speaker 01

  Yeah. And the grand eventuality, it is obvious.

• 55:05Lex Fridman?

  Of the, of human civilization, this whole human experiment we have here, we should be expanding out into the cosmos.

• 55:12Speaker 01

  A hundred percent. So I think the big mission, if we're measuring SpaceX's success on getting to Mars or not, I think they'd have a really hard time continuing to fulfill that drive without Elon at the helm. Now, I think there's a certain balance and beauty of Elon, specifically when it was Tesla and SpaceX, where Elon will go in, you know, have mild tornadoes around the factory and the engineering, you know, and like mix everything up and things get sometimes just totally thrown together, you know, and totally just like get it done, just to get it done and start- Moving in that direction and then he'll leave and go do that same thing, you know, at SpaceX or Tesla vice versa.

• 55:54Speaker 01

  And then there's a little bit of a calm where people come back in and they fill in those gaps, you know, and I think that's kind of always been a pretty healthy thing, honestly, is like, I think if he is too focused on on any one thing, it almost is like he'll spin too much, you know, like it's like.

• 56:09Lex Fridman?

  Like too many tornadoes.

• 56:10Speaker 01

  Yeah, too many tornadoes. And and I think it could almost be like, you need someone to come back in and like, you know, like backfill almost because I've heard definitely stories of like, like, well, probably a good, a good example would be last, last, well, was that last year or two years ago, 2022? Yeah. Was that? Yeah. I know. 2021. They did the first full stack of Starship Super Heavy. And they called it the big surge. All of a sudden, like thousands of SpaceX employees, you know, came down to Starbase. And they just started building like you wouldn't freaking believe. I mean, it's just things going crazy. BP, it was actually in the middle of that first interview I did with him, it was in the middle of that surge. There was like commotion like you wouldn't believe. You couldn't hardly talk because there's just so much going on.

• 56:55Speaker 01

  People just welding and blah, blah, blah, you know. Everything they did during that period was basically scrapped. Because it was just not done very well. But they got a fully stacked Starship rocket out on their launch pad. You know, and it set, I think at some point you kind of have to stabilize some things enough and just say like, this is what we're doing to catalyze some things and say, now do this. It's almost like, do it for fake, now do it for real, almost.

• 57:23Lex Fridman?

  It's funny because through that time, because I had a lot, a lot of conversation with him, I think that process was hugely stressful. There was a sense, I don't know where that sense is today, but there's a sense that Starship is going to be very hard to pull off.

• 57:37Speaker 01

  Yeah, that's still.

• 57:38Lex Fridman?

  Borderline impossible to pull off. And and that was really weighing heavy on him and the team and everybody.

• 57:44Speaker 01

  Yeah.

• 57:45Lex Fridman?

  So like to have this chaos of development is fascinating.

• 57:48Speaker 01

  Yeah, big time. And I think they really had to push. You know, if they hadn't done that, if they hadn't done that big push. You know, we might only be now seeing a rocket stacked for the first time. You know, it might be a lot more finished rocket, a lot more high fidelity, a lot more flight worthy rocket finished and stacked, but and they might not have to walk stuff backwards. But at the same time, like you do have to, in this world, you do have to push really hard to make rapid iteration, rapid change in progress. So it's, it's interesting. I don't know.

• 58:24Lex Fridman?

  So lingering on that, another question I really should ask you because of you've seen, you've been in awe of the amazing development of space travel technology over the past few years. What do you think about Elon buying Twitter? So in this perfect balance, optimized reallocation of tornadoes throughout the various efforts in human civilization, do you think, do you worry about his involvement on Twitter?

• 58:59Speaker 01

  I mean, personally, I just, I see that as a lot less important than, and personally for me inspirational than Starship and, you know, the work done at SpaceX and Tesla. To me, those were two very impactful and really, really just generally like, you know, they're uniting, like, you know, something to rally around, get excited about, rally in, and just like a future to look forward to.

• 59:23Lex Fridman?

  Yep.

• 59:24Speaker 01

  You know, the idea of we're going to be building the world's most powerful, biggest rocket ever, and it's eventually going to be able to get humans on Mars for the first time. And we're going to transition the world into fully sustainable, awesome, just totally badass cars that do all these cool things. To me, those were like, that brought a sense of unity and a sense of like, we can do this. Personally, I just don't think that a social media, no matter what it is, I don't see that in a social media. And I don't, I don't see any sort of politicking as ever, anything that's really ever a uniting thing.

• 59:58Lex Fridman?

  I understand that. I totally agree with you, especially with space, how inspiring it is. I have to push back. I do think the impact of social media, the basic level of

• 1:00:12Lex Fridman?

  Meaningful connections of this collective intelligence that we call human civilization through the medium of, you know, digital communication, which is social media, I think that can have a huge impact. It could be the very vehicle that increases the inspiration that SpaceX doesn't.

• 1:00:28Speaker 01

  Oh, 100%.

• 1:00:31Lex Fridman?

  The thing I've criticized them a bunch for is like, why bring politics into this? So the political divisions that we see on Twitter feeding them is tricky.

• 1:00:45Lex Fridman?

  It's tricky to sort of understand what is the value of that? What is the contribution of that to this whole effort we got going on? So that's been, that's been a big challenge. But that said, like, again, this tornado, the number of tornadoes in social media, I think is really important because social media has such a huge impact on us as a society. And to have a transparent, have a bit of turmoil. You know, it's like Tom Waits says, I like my town with a bit of drop of poison, with a little drop of poison. So like a little bit of that shake things up, I think might be really healthy.

• 1:01:26Lex Fridman?

  I just worry about the long-term impact on the whole Mars project through that. And so, but you know what?

• 1:01:34Lex Fridman?

  This life, one of the reasons it's fun is through the chaos, you like, none of us know how it's going to turn out. And hopefully, we try to help each other to make sure it turns out well.

• 1:01:47Speaker 01

  And this really isn't like anything about my personal like politics or anything like that, but really just generally, any of my friends that are like, the first thing you hear about them in their day is something that happened in politics or something that some world leader is doing or not doing or saying and not saying. I just don't find that to be the most important thing, really. I know that obviously that can affect a lot of people that has big, real world consequences. Politics do. But like, I just, and this is just me. I'm such a like, oh, come together, you know, cheerio kind of guy. That I just really think like, you need something bigger than bickering about what, you know,

• 1:02:26Speaker 01

  what people said and did and what they voted on and all this stuff to really push humanity forward. Like I, you know, I know that politics and their, and by extracting that social media can affect things like spaceflight and even our planetary defense, like being able to defend ourselves against asteroids. Like if politics has their way and everything goes to crap and we don't even get to, you know, yeah, we're not going to be able to, you know, continue spaceflight and things like that. But like, I don't know. I just think there's better ways to do it and more uniting ways to do it than, than, you know, what feels like immature name calling sometimes, you know?

• 1:03:03Lex Fridman?

  Yeah, I think the political bickering that most people talk about, that's on top of most people's minds is the thing that'll be completely forgotten by history. It has actually very little impact. Yes, politics matters, but like 1% of it. I think most of it is just political bickering, the push and pull of the red team and the blue team. And then the, the news media that feeds off the division for the attention. And it's just like a fun athletic event almost with the, with the blue team and the red team. So that you kind of have to have a historical perspective on it. Like most things will not really have a significant impact. And we should focus on development of science, technology, engineering, which is the thing

• 1:03:48Lex Fridman?

  that grows the pie.

• 1:03:49Speaker 01

  A hundred percent.

• 1:03:50Lex Fridman?

  This is what the economists know well.

• 1:03:53Speaker 01

  Yeah.

• 1:03:53Lex Fridman?

  Just the innovation, the engineering, that's what actually makes everybody richer.

• 1:03:56Speaker 01

  Yeah.

• 1:03:57Lex Fridman?

  This kind of political bickering is just eating the pie.

• 1:04:00Speaker 01

  And not just richer, but it improves their lives. You know, we can look at every modern technology that is bestowed upon us today, air conditioning, electricity, internet access, fresh, clean water, running water, blah, blah, blah. You know, a hundred years ago, so many of the things that I listed either didn't exist or were only accessible by the ultra wealthy. You know, and it's through the innovation of technology and engineering and education that we are able to have it be that even someone below the poverty line in the most of the developed world will have a good number of those things in their life. And that's just continuing to increase and continue to get better. So I think, yeah, that's, to me, that's in the grand scheme, more important, but to each their own.

• 1:04:41Lex Fridman?

  Speaking of amazing technological development, you have, you have a few videos on this, but how does a rocket engine work? You've, you're, you're wearing some of the instruction manuals, but for one, one type of it, like what, what's the fuel? What are the kinds of types of different rockets that you can kind of give an overview?

• 1:05:03Speaker 01

  Yeah. Ultimately, a rocket engine converts high pressure and heat into kinetic energy. Like, that's the only real job of a rocket engine is to take high pressure gas, hot high pressure gas, very energized, there's a lot of energy involved, and then literally turning that into molecules shooting in one direction into kinetic energy. So, um, yeah, what you do, basically, you know, I mean, the simplest version of it is, of course, like famously a balloon. You take a balloon, you fill it up with air, you've got a pressure, you let go of it, some of the air shoots out in a general direction-ish, you converted that pressure into kinetic energy. Now, if you start scaling that up, you know, you can continue to do something like that,

• 1:05:46Speaker 01

  like, um, cold gas thruster would be kind of the most simple and easiest rocket engine to make, would be a cold gas thruster. And all that is, you literally just take air, or specifically nitrogen, because it's a little bit more dense than all the others, or, you know, and it's the majority of our atmosphere, you can, or sorry, it's more sparse, you can condense that down, sort of a really high pressure bottle, and then just literally shoot it through what's called a di-laval nozzle, which is something that chokes the flow a little bit, gets it to be, takes it and gets it into supersonic speeds. Once it's at supersonic speed, you actually can't choke it down anymore, you'll just constrict the flow of, of mass flow, you'll constrict the airflow. So you actually go opposite, you start making it wider.

• 1:06:29Speaker 01

  And once it's already at supersonic speeds, if you expand it and make it wider, it actually gets faster and faster. So at first, you know, when it's subsonic gas, You start shrinking, you can strict the flow, you know, it's actually speeding up just like, you know, a highway. If you go from, or any of these examples, like a water hose, you, you know, if you pinch it down, you want to flow the same amount of water from point A to point B through a smaller pipe, you can, you can flow more water, the same amount of water from point A to point B with a smaller pipe, it just has to go faster. So obviously you can constrict it, but at some point you actually get to a physical limitation and that happens to be the speed of sound. Once it gets to the local speed of sound, you can then actually do the opposite. You actually expand it back out and you're continuing

• 1:07:09Speaker 01

  to convert the, the pressure into velocity at that point, but it's now supersonic. And what's interesting is while you're doing that, you're actually cooling it down too. Each, each bit of that pipe that you're making wider and wider and wider, you're cooling down. So the more heat energy you have to work with, the more work you can actually do. So at some point, a hot, high pressure rocket engine is the best source of, like, that's the ultimate amount of work you can do.

• 1:07:35Lex Fridman?

  And the nozzle, so as you're saying, there's a bunch of different design options, but it's a critical part of this.

• 1:07:41Speaker 01

  Yeah.

• 1:07:42Lex Fridman?

  How you do that conversion.

• 1:07:43Speaker 01

  It's basically like, how much can you convert is really like the ultimate game? How much pressure and heat can we convert into thrust? Like, that's really, at the end of the day, that's what a rocket engine is. So you have to have a powerful enough rocket engine to actually lift the rocket and, well, a rocket is mostly just fuel. It's like 90, 90 plus percent just the weight of fuel. So you just have to lift the fuel that's going to take it, you know, into orbit.

• 1:08:09Lex Fridman?

  And that's the thing specifically for rockets, you're saying generally rocket engines, but for the task of going to orbit, you're fighting gravity, earth gravity, which is fundamentally different than moon gravity or.

• 1:08:23Speaker 01

  Yeah.

• 1:08:23Lex Fridman?

  Mars gravity.

• 1:08:25Speaker 01

  Yeah.

• 1:08:25Lex Fridman?

  Uh, or like you said, traveling out to space. Earth has a pretty intense. Gravity.

• 1:08:31Speaker 01

  It's.

• 1:08:32Lex Fridman?

  To overcome.

• 1:08:33Speaker 01

  We're lucky because if I think if it's 10% either way, like 10% harder, it'd be like, oh, we could still do it. You know, we'd still with our current technology, we'd still be able to get stuff into orbit. Man, things like reusability and this, you know, commercialization, the success that we've seen in the last 10 years, we'd just be on two thin margins, I think. 10% easier and we would have been like, I mean, it's just like totally different. It's so much, so much easier. It's like this big, you know, sliding scale and 10% in either direction, we'd be either screwed or really happy, you know? Uh, as far as getting into space. So it's just hard enough that it, things like fully reusable becomes very, very, very difficult.

• 1:09:11Speaker 01

  I think it's completely achievable. Uh, we have all the pieces to make it achievable. It does not disobey any laws of physics. It does not disobey any, there's no like hard stops. It is just very, very, very hard. And so ultimately, yeah, like on earth for the first bit of, of launch, again, when, when the rocket's pointing straight up and it, and the engines are pointing straight down, pointing end up flaming and down, you're fighting gravity. And so that's kind of your biggest enemy, um, outside of the earth's atmosphere too.

• 1:09:37Lex Fridman?

  So what kind of, uh, sources of fuel is there? So there's chemical rockets, liquid solid gas, hybrid, uh, there's electric. So what, what are the kinds of fuels we're talking about? What are oxidized? What, what, can you just explain your shirt? I guess.

• 1:09:53Speaker 01

  Yeah.

• 1:09:54Lex Fridman?

  The components of your shirt.

• 1:09:56Speaker 01

  So, uh, so really, I mean, fuels, it's, there's kind of two terms. Well, you'll generally hear the word propellant being used. It's anything that is used to propel a spacecraft or used in a rocket engine. So, um, you have to have, you know, you can have a fuel. You're, you have to have a fuel. You have to have an oxidizer and you have to have a spark to actually get those things burning. And that's just a general law of like the universe. You have to have fuel and oxidizer and a spark. Now, some fuels will by themselves spark like hypergolic fuels. But ultimately, you're always left with some kind of fuel oxidizer in a spark. So the general ones used most often in rockets, liquid oxygen is kind of the king of. Well, there's better oxidizers, but they're extremely, extremely hard to work with like fluorine.

• 1:10:41Speaker 01

  But generally liquid oxygen. So you just chill oxygen down to its liquid state minus 183 degrees Celsius. So it can be dense enough to store in tanks. You know, it's a thousand times more dense when it's in a liquid than it is as a gas. RP1, which is basically kerosene, is a very common fuel. Another common fuel nowadays is methane, liquid methane. Liquid hydrogen is another, it's the most efficient potential for the most efficient since it's one of the lightest molecules.

• 1:11:12Lex Fridman?

  So I think, correct me if I'm wrong, but Falcon 9 uses kerosene. And then Starship uses methane.

• 1:11:20Speaker 01

  Yep.

• 1:11:21Lex Fridman?

  Liquid methane?

• 1:11:21Speaker 01

  Yep, for fuel and they both use liquid oxygen for their oxidizer.

• 1:11:24Lex Fridman?

  For the oxidizer, okay.

• 1:11:25Speaker 01

  Yep. But then, you know, if you get into hypergolic, you'll normally have nitrogen tetroxide, which is your oxidizer and some form of hydrogen for your fuel.

• 1:11:36Speaker 01

  There's solid rocket propellants, like solid rocket boosters, and those are actually premixed. Your oxidizer is inherently like baked, literally like kind of baked into the sludge of of fuel.

• 1:11:46Lex Fridman?

  So like for SpaceX, it's all chemical liquid fuels?

• 1:11:51Speaker 01

  Yep, yep.

• 1:11:51Lex Fridman?

  So how many solid based fuels are there? Is that they still being used today or most rockets?

• 1:11:58Speaker 01

  Yeah, and the United States really is the only ones that, well, the only ones that I guess early on, because it was really just the Soviet Union versus the United States. The United States started to use solids pretty early on. They're simple and easy, but these days, like, you know, you'll still see them kind of as. Traditionally like boosters, like they're used to just help get something off the ground or help give it a little extra boost. So the space shuttle famously had those two huge white solid rocket boosters attached to the orange fuel tank. Those are solid rocket propellants. Things like the Atlas V can have up to five smaller solid rocket boosters. There's very few rockets that use a pure, at least these days, that use a pure solid rocket motor for its first stage. There still are, especially in China, there's a lot of

• 1:12:42Speaker 01

  startup rocket companies that kind of use just missile technology. You know, they might use like a, there might just be a variant of an ICBM that just use solid rocket fuel because it is very relatively easy to develop. You know, model rockets use solid rocket motors and stuff like that. So they're, they're still around, but they're just not as elegant and not as, uh, yeah, not as, as used these days, I'd say.

• 1:13:03Lex Fridman?

  So what are rocket engine cycles? Getting, I think getting more to your, towards your shirt question. You have a really good video called that, I mean, a lot of your videos that are technical are just exceptionally well done. So I just, I think you deserve all the props you get. I mean, thank you for, for doing this work. Really, really, really, really well done. So it's called rocket engine cycles. How do you power a rocket engine? And you go through all the different options. Is there something you could say about open cycle, closed cycle, full flow, all the different variants that you can use words to explain?

• 1:13:40Speaker 01

  Yeah, without all the pretty pictures.

• 1:13:41Lex Fridman?

  Yeah, without the pretty pictures.

• 1:13:43Speaker 01

  So ultimately, you know, like we said, we, your ultimate goal is you want to get heat and pressure into an engine. So obviously at some point you can either make really thick tanks of your rocket. You can like get it so thick that you store the propellants in really, really high pressures. But obviously like that doesn't scale very well. At some point your rocket's so heavy, you can't even leave the ground or you know, it's just so much of your mass is just literally the walls of the rocket. So at some point people realize, hey, we could actually just pump the fuels and the oxidizer into the engine at a high pressure and increase the pressure through a pump. Now, obviously a pump's going to require energy. You have to get that energy from somewhere. And again, at some point people were like, well, rockets are, there's already rocket fuel here, you know, we'll

• 1:14:26Speaker 01

  just use some of the energy from the rocket fuel to spin these pumps. So that, that would be considered like open cycle, closed cycle, full flow stage combustion cycles are, are ways to. Tap into the propellant, actually, and then there's tap off expanders. Like, I mean, all of them kind of do the same thing, but you end up at some point spinning a turbine. You know, a turbine can take some of the heat energy and the, and the, and the pressure of an engine, and then they can, that can be connected to a shaft to pumps, and those pumps can, you know, increase the pressure of the propellants and force it into the combustion chamber. Now, the difference between open cycle, closed cycle, full flow, all those is what happens

• 1:15:07Speaker 01

  after the gas has flown through the turbine. So after you've used the turbine and spun up the energy, you know, spun up the engine, what happens to that gas? So in an open cycle engine, you basically have like a separate, small rocket engine, in a sense. It's a gas generator, they call it. And that will be used to create some, you know, take a little, we'll say 10% of your, the propellant flowing to the engine. Instead, you reroute it to like a smaller rocket engine called the gas generator. You point that at your turbine, and that will spin your turbine up to, you know, ridiculous speeds, 30,000 plus RPM. And then, after it spins, it's wasted most of its, its energy, you know, and it's just dumped overboard. That would be open cycle.

• 1:15:48Speaker 01

  You're not worrying about it after that point, but you are left with a lot of unburnt, un, you know, unused fuel. A good amount of that fuel is just completely, and especially because the turbine, you, you have to keep it from melting. So you can't run it at like optimal ratios. Not necessarily stoichiometric. In a rocket engine, you actually don't want it to be near stoichiometric, where you're releasing all the energy. You actually want to release, you actually want to be throwing out the lighter molecules, so it can be shot out faster, generally in the engine. So, but in order to have a turbine survive, you have to actually cool, you have to have the, the gas going through it. It can't be stupid, stupid hotter, else you're just going to melt your turbine. So they normally, especially in the open cycle,

• 1:16:30Speaker 01

  you just run it really fuel-rich. So there's a lot of extra fuel being pumped into it that will keep the temperatures at a reasonable, you know, at a reasonable temperature. So you end up with this like dark sooty smoke pouring out of that gas generator, that's just unburnt fuel, just wasted fuel. It never got a chance to be used. Oh, interesting. You know, like in the combustion chamber. It's not, it's not being used to propel the rocket. You know, it's just being used to cool down the, the propellant that's being used to spin the turbine, that's being used to spin the pumps, to push a lot of propellant into the engine. So. You know, it doesn't take too long before, you know, you're a greedy rocket scientist being like, look at all this wasted propellant, all this potential energy that's just literally being spewed out the side of the rocket. So that's where the closed cycle comes in.

• 1:17:14Speaker 01

  So now you have to get that propellant, take it from basically what was being wasted through the turbine, and you're going to try pumping it back into the engine. Now, you don't literally just pump that, that gas that's, you know, that hot, that gas into the engine because it's actually way too low of pressure compared to the main combustion chamber. And by that point, by the time it's gone through the turbine, it's lost most of its pressure and heat to the turbine. So if you tried pumping it into the engine, you know, just taking that pipe and sticking it right into the combustion chamber, that much higher pressure, hotter combustion chamber would just go backwards and it'd stall out the engine and blow up the engine and whatever, what have you. So what they actually do is they normally will send, there might be some variations of this, but the general concept is you actually flow

• 1:17:57Speaker 01

  all of your fuel or all of your oxidizer through the turbine. So that would be closed cycle. So there's fuel-rich closed cycle, which would be you're flowing all of the fuel through the turbine, or there's oxidizer closed cycle, which is where you're flowing all of the oxidizer that's going into the engine through the turbine. Now, the trick here is you have to have that turbine after it's done its work. So after it's taken some of the potential energy, some of the heat energy from, we're not calling it a preburner, by the way, instead of it being a gas generator, you now call that device that's, that's creating pressure to spin the turbine, you're now calling that a preburner because it's just going, going to preburn some of your fuel or some of your oxidizer. The trick is that

• 1:18:38Speaker 01

  has to be, by the time it's gone through the turbine, it has to be higher pressure than the combustion chamber, because otherwise it's going to go backwards still. So you really have to get that preburner up to ridiculously high pressures, like at least 20% higher than your main combustion chamber. And these combustion chambers, you know, we're talking about engines that are at, you know, 200, 100 to 200, even in SpaceX's Raptor engine, up to 300 bar in the main combustion chamber. So that's, what is that, 4,500 PSI, basically, insane amounts of, of pressure inside these combustion chambers. So your turbine has to be even above that, or your, your gas generator or your preburner, sorry, has to be higher pressure than that even, in order to have the flow going the right direction through the engine.

• 1:19:22Speaker 01

  So now you'll you'll have those closed cycles. You'll have fuel rich, you have oxidizer rich. The tricks now, you're starting to get, it's crazy. There's just so many compromises. Every little decision you have of like, oh, I did this. Now I know, crap, it's gonna do this. For instance, fuel rich, if you ran kerosene, fuel rich, you know how I mentioned soot coming out of the gas generator? Well, if you run soot through your, through your engine like that, and had it go through your injectors, like back into the engine, it'll clog the pores of the injectors, and it'll end up blowing up the engine. The soot itself is so damaging that you can't really run a fuel-rich kerosene engine.

• 1:20:00Lex Fridman?

  What exactly is soot? So it's like fuel, somehow mixed up with the smoke? Like what? I wonder what, what is it chemically? It's some weird?

• 1:20:09Speaker 01

  It's mostly just carbon. It's mostly just that carbon.

• 1:20:12Lex Fridman?

  That dark smoke.

• 1:20:13Speaker 01

  Solid, solid chunks of carbon. And it can cake up and just literally like, you know, like, yeah, it's, it's, it's like ash almost, you know, like, at some point, you know, especially under those high pressures and high temperatures, it can physically build up and, you know, turn into like stalagmites and stalactites of, of carbon, really hard, you know, forged in a rocket engine carbon.

• 1:20:36Lex Fridman?

  I wonder how you figure all that out, too. It has to be experimentation. Some of that is chem- chem- like theoretical, but like, you're gonna have to build the thing at scale and actually test it.

• 1:20:45Speaker 01

  Trial and error.

• 1:20:46Lex Fridman?

  There's many decades of trial and error.

• 1:20:49Speaker 01

  And many pieces of engines that you're trying to piece back together, going like, what the hell happened here?

• 1:20:53Lex Fridman?

  Yeah, what happened?

• 1:20:54Speaker 01

  Yeah.

• 1:20:54Lex Fridman?

  Okay, so, uh, so that's closed cycle. So how do we get to full flow?

• 1:20:58Speaker 01

  So in either of those situations, you're still actually just having the opposite. So if you're fuel-rich, you know, all the fuel is going through the turbine, but only a tiny bit of oxygen is actually being put into that pre-burner to, to spin the pumps. And the rest of the, the rest of the oxygen is actually going through the pump, the primary pump, and straight into the combustion chamber. Now, full flow, the idea is you're going to actually pre-burn both your propellants. Both your propellants are going to go through a pre-burner, and they're both going to end up spinning one of the pumps. So you'll have a gas, a fuel-rich pre-burner, and you're going to have an oxygen-rich pre-burner. Each one of those is going to get just, you know, they're gonna heat it up just enough and get it up to just enough pressure. To spin up that turbine as fast as they need to do to get the pumps up to the right

• 1:21:43Speaker 01

  pressure and still have enough pressure through the turbine to overcome the pressure inside the main combustion chamber. And they're both going to arrive, both your fuel and your oxidizer are going to arrive in the main combustion chamber as hot gases already. So what was liquid oxygen is now gaseous oxygen. What was liquid methane is now gaseous methane. And they're meeting in this combustion chamber at still ridiculously high pressures again.

• 1:22:07Speaker 01

  For SpaceX's Raptor engine, they're meeting at 300 bar, insane amounts of pressure. And then they then they combust from there on. And because they're already a gas gas interaction, they're happy to burn. They're ready to, they're ready to burn, they're, they're ready to mingle as opposed to having a gas liquid interaction, which is what's a lot more normal. You know, you'll have two different states of matter and they just might not, they might take a little more coaxing to, what's that word?

• 1:22:32Lex Fridman?

  Coaxing?

• 1:22:33Speaker 01

  Yeah.

• 1:22:34Lex Fridman?

  Coaxing?

• 1:22:35Speaker 01

  Coaxing?

• 1:22:36Lex Fridman?

  That doesn't sound like, that doesn't sound correct, right?

• 1:22:38Speaker 01

  Coaxing.

• 1:22:38Lex Fridman?

  Coaxing, yeah, yeah.

• 1:22:41Speaker 01

  All right. I don't know. We'll cut that at post.

• 1:22:44Lex Fridman?

  We'll have Morgan Freeman overdub us.

• 1:22:46Speaker 01

  Yeah.

• 1:22:49Lex Fridman?

  The fascinating thing is they're coaxed as gases in the combustion chamber.

• 1:22:54Speaker 01

  Why can't I think of that word? But yeah, they, they just take a little bit more, it takes more time in the combustion chamber to have a liquid and gas interaction like mixed together and unleash as much of their energy as you can before it exits the system.

• 1:23:07Lex Fridman?

  Are some of the trade offs here in terms of efficiency, which, which, which is most efficient? And then also complexity of the design and the engineering and the cost of the design and the engineering? Like, what are the different trade offs between open cycle, closed cycle and full flow?

• 1:23:20Speaker 01

  Yeah, it's, it's a pretty, it's kind of like a, what's the, the bears, the Goldilocks? You know, like, it's like, you kind of generally, the easiest is open cycle. Cause you know, you're just expelling the, the exhaust gas, the gas generated exhaust, you're not having to worry about it. You just spin up that thing as much as you need and deal with it, right? No big deal. Closed cycles offers 10 to 15% greater performance generally because you know, you're not wasting that propellant. And but it's it's complicated. It's a lot more complicated, especially if you're doing oxygen-rich. Now you're having hot gaseous oxygen in your engine, which just generally wants to react with everything.

• 1:23:59Speaker 01

  It's just a recipe like hot oxygen is just a recipe for things to catch on fire that shouldn't be on fire. So metals, you know, under those conditions, lots of times will just spontaneously start burning. You know, you'll actually turn your metal and it will now become fuel. You'll be engine-rich before you know it because your hot oxygen is eating and using that engine as fuel, basically. So oxygen-rich is generally very hard, but that is what the Soviet Union ended up doing with almost their entire line of engines was close-cycle oxygen-rich. But, you know, so those two are kind of generally hard, but offer great performance benefits over open cycle. But at the end of the day, you know, full flow is by far the it's the ultimate of all of them.

• 1:24:43Speaker 01

  It's the most difficult, but it's also has the most potential to be the most efficient.

• 1:24:47Lex Fridman?

  Starship, the Raptor II, the why is that engine using full flow?

• 1:24:52Speaker 01

  Because it's the best. I mean, it's just physics-wise, if you're trying to extract as much energy out of your propellants, there there just isn't another cycle type that that is better than it. But of course, it's very, very hard to develop, you know, so far to date. The RD-270 in the 60s was built. There is a powerhead demonstrator built in the United States in the in the 90s and early 2000s, I think, maybe just the early 2000s. That was just the just the power, just the the pumps and the turbines and the preburners, no chamber, no nothing. That was a big deal. Only the United States took, you know, millions of dollars to just develop that. And then their SpaceX's Raptor engine.

• 1:25:27Lex Fridman?

  So you talked about the combustion chamber and how damn hot things get. High pressure, a lot of heat. How do you keep the thing cool? You have a great video on this. How do you get it from from what do you call it? Metal-rich, engine-rich, engine-rich from like the the metal from melting?

• 1:25:50Speaker 01

  Well, one of the ways is to let it be engine-rich. There's actually you can use a blade of cooling. You can literally let make the walls thicker than you normally make it. Make it out of a material that will blade away, that will kind of chip away and takes in the heat away with it. It's very, again, primitive, and it's actually what SpaceX first used on their first Merlin engines. They used a blade of cooling. So it's basically a carbon nozzle and you just let it get the carbon, the inner layer of the of the engine was not, it was carbon. And you just let it get. Chewed away and eaten away and that's just something you factor in. Uh, it's not a very elegant and it's definitely not reusable in that sense.

• 1:26:27Lex Fridman?

  So there's probably really good models about like how it melts away, the rate at which melts away to know what thickness.

• 1:26:34Speaker 01

  Yeah.

• 1:26:35Lex Fridman?

  But boy, it's a dangerous.

• 1:26:37Speaker 01

  I just.

• 1:26:37Lex Fridman?

  It's just part of the design.

• 1:26:38Speaker 01

  Seems so silly. So obviously you probably, you know, it's again, it's not the most elegant and the problem to your, your geometry physically is changing too. Cause as you're eroding the walls, now things like your expansion ratio or the ratio between your throat and the nozzle exit is changing.

• 1:26:53Lex Fridman?

  Yeah.

• 1:26:53Speaker 01

  Because the thickness, like the throat's diameter is actually like, everything's changing. So it's, it's not great.

• 1:26:59Lex Fridman?

  It might, might not be melting away uniformly. There could be some like weird pockets for aerodynamics stuff. There's just a bunch of chaos just can, which.

• 1:27:07Speaker 01

  I can't imagine having to like figure all that stuff out, honestly.

• 1:27:10Lex Fridman?

  Yeah.

• 1:27:12Speaker 01

  So the, uh, the more elegant thing to do, there's, there's a couple of other things you can do, but the kind of the most common one, especially when we're dealing with liquid fueled rockets, is something called regeneratively cooling. And the, the idea is you basically just flow fuel or fuel or oxidizer through the walls of the, of the nozzle in the chamber, um, before they go through like into the injector, into the actual combustion chamber. By doing that, you're, you're taking heat out of the, you know, you're, you're taking heat out of the metal of the walls and you're putting it into the propellant. So you're typically heating the propellant up, which is remember when I said there's gas interaction versus a liquid, like liquid gas lots of times, even if you pump them both at, you know, as, um, they, you know, are both being pumped as liquids.

• 1:27:55Speaker 01

  By the time it goes through the walls of the chamber, lots of times, one of them is phase changed into a gas. So now you do have that gas liquid interaction. Um, that's because they're using that, the fuel or the oxidizer to, to cool the walls of the, of the engine. So when you look at a rocket engine, although it looks like, you know, a nice beautifully uniform cylinder, you know, smooth thing. Um, there's either, there's sometimes like a, the channels actually like milled into the walls that they run fuel through. And even though they're tiny, you know, they can be like two, three millimeters thick. They'll actually still have a channel that goes down and U-turns and comes around and comes back. All the way down to the tip of the nozzle and everything. So it's, it's just insane that, you know, the.

• 1:28:32Lex Fridman?

  Isn't that's pre-designed and that that's, that's like, uh, so they design those channels.

• 1:28:37Speaker 01

  Yeah.

• 1:28:38Lex Fridman?

  There's probably some optimization there, like how the flow happens.

• 1:28:41Speaker 01

  Well, especially because you you're thinking about a conical thing or like a semi conical thing where the the area is getting smaller and smaller and smaller, you're flowing the same amount of propellant through it as you are down. You know what I mean? Like the propellant has to. So they have all these unique things like, you know, sometimes different manifolds where they'll inject more or less fuel in certain areas and.

• 1:29:01Lex Fridman?

  There must be like propellant simulation software because they can't surely can't like test this on actual physical.

• 1:29:10Speaker 01

  Well, back in the day, they had to just build it.

• 1:29:12Lex Fridman?

  Well, you mean back in the back in the day, walked uphill in both ways. It was like, I mean, like any anything back in the day before computers, where you like had like.

• 1:29:26Speaker 01

  You just had to do it.

• 1:29:27Lex Fridman?

  And like your simulation or modeling was like a sheet of paper where you're like calculating stuff.

• 1:29:32Speaker 01

  Well, but you can. Heat flux, you know, like you can literally see how much energy and how much heat is inside the combustion chamber, how much, you know, and that is a measurable thing even without a computer. Now, I'm not near smart enough to do any of this. Like I've never tried measuring the heat flux of anything. I barely even know what that means. I'm just smart enough to regurgitate it.

• 1:29:52Lex Fridman?

  You haven't lived.

• 1:29:54Speaker 01

  But that is something that people would calculate and they find out, okay, copper, you know, does a better job of transferring the heat between the walls of it and into the propellant, blah, blah, blah, blah, compared to X, Y, Z. So, you know.

• 1:30:06Lex Fridman?

  Materials, people, I like, I've met just in all walks of life, especially just throughout MIT, through everywhere, where there's some people are just like a hundred X smarter than anyone you've ever met at a particular thing. Like you mentioned copper, they'll know the heat dissipation through different materials. They'll understand that like more than, it's like, holy shit, it's possible for a human being to deeply understand a thing.

• 1:30:35Speaker 01

  Dude, aerospace is full of that. You'll have people that are so niche in some thing that no, like the average person has never even remotely thought of, yet this person has done it 40,000 different ways in a, you know, in a, an environment being like, well, we found out that if we turn it four degrees that way and add 4% niobium, you know, like just things you're like. What is your life? And how do you know this?

• 1:31:00Lex Fridman?

  And the funny thing about them, they usually don't think it's a big deal.

• 1:31:05Speaker 01

  Yeah.

• 1:31:05Lex Fridman?

  They're usually like, they're so nonchalant about it that if you don't actually, you have to know enough. You actually have to know quite a lot to appreciate how much more they know.

• 1:31:17Speaker 01

  Yeah.

• 1:31:17Lex Fridman?

  Because otherwise you won't even notice it. Because our popular culture doesn't celebrate the intricacies of scientific or engineering mastery, which is interesting. There's all these people that lurk in the shadows.

• 1:31:29Speaker 01

  Oh, I know.

• 1:31:30Lex Fridman?

  They're just geniuses.

• 1:31:31Speaker 01

  Yes.

• 1:31:31Lex Fridman?

  Like you see, you have like the LeBrons who are like good at basketball. So we understand that they're good at basketball. They do this thing with the ball and the hoop and they do like it really well. But then a lot of other people under pressure, like we celebrate.

• 1:31:43Speaker 01

  It's this big public spectacle.

• 1:31:44Lex Fridman?

  Yeah.

• 1:31:45Speaker 01

  Look how great they are. Yeah.

• 1:31:46Lex Fridman?

  But like the people like, yeah, as at these aerospace companies and NASA, SpaceX, the kind of stuff they're doing, just the, I mean, there's geniuses there. And it's actually really inspiring. I mean, I've, I've interacted with a lot of brilliant people in the software world. And maybe because I don't deeply understand a lot of hardware stuff, materials engineering, mechanical engineering, those people seem like so much smarter. I mean, it's always like the grass is green or whatever the expression is. But there's a depth of understanding that engineers have that do like mechanical engineering. That's just awe inspiring to me.

• 1:32:24Speaker 01

  Not to get too like, I don't know what the word would be, introverted or something or whatever. But that's actually kind of the whole point of Everyday Astronaut. Like, that's almost the whole point of what I do each year. From the beginning, I did a thing called the Astro Awards, trying to be like an award show, hoping to lift up and celebrate and shine a spotlight on the people that are actually doing the hard work and try to treat them like the rock stars that they are that we don't know about. And I think that's one of the things that for sure, I think, you know, I think Elon definitely helped make spaceflight cool. Helped make that like a celebration thing where people are physically out cheering for rockets and science and space exploration. But I think that's just the beginning, you know? I think like this should be a thing where the general public

• 1:33:09Speaker 01

  looks to these people as the coolest ones, as the coolest places to work, as the most important things. You know, sports are great and everything. I'm a big Formula One fan and things like that, but. You know, at the same time, like, we should be celebrating the people doing this crazy work, you know, clocking in countless hours, just trying to figure out this one little thing that's going to help us further our understanding.

• 1:33:29Lex Fridman?

  I mean, what's cooler than a giant thing with a really hot fire that goes boom and goes up into the air? I mean, like, there's no, it's, it's like, to me, like, bridges are inspiring. It's like incredible architecture design and like the humans are able to work against nature, build these gigantic metal things, but like rockets.

• 1:33:54Speaker 01

  Yeah.

• 1:33:54Lex Fridman?

  With like a tiny little humans on top of them.

• 1:33:57Speaker 01

  Yeah.

• 1:33:57Lex Fridman?

  Flying out into space. It's like, it's the coolest possible thing. Everything comes together, all the different disciplines come together for the high stakes drama of, you know, riding that super powerful thing up away from the thing we call home, Earth. It's like, it's so amazing.

• 1:34:15Speaker 01

  Exactly.

• 1:34:15Lex Fridman?

  So freaking amazing.

• 1:34:16Speaker 01

  Well, I think that's kind of part of my like story arc, because I, I just used to be a huge car and motorcycle guy. Like, I just loved, you know, things that go fast and, you know, are loud and go fast and make lots of power. And at the end of the day, like, at some point, you realize, nothing goes faster and it's louder and makes more power than a rocket. You know, and I think that's, I think that's kind of where, where I eventually just ended up, you know, wound up there just because there is nothing cooler than that.

• 1:34:41Lex Fridman?

  Yeah, that's the ultimate level of reach as a car guy is to become a rocket guy.

• 1:34:45Speaker 01

  Yeah, a hundred percent. And at some point, some car guys literally become rocket guys and strap rockets to cars and try and break land speed records, you know, like it's, it's, it's the same universe here and yeah.

• 1:34:55Lex Fridman?

  So Elon, with your conversation with him on, on the Raptor two, was talking about, you were talking about, like, there's an excessive amount of cooling to be on the safe side as you're developing the engine. What kind of cooling was that?

• 1:35:08Speaker 01

  So that would be film cooling. So remember how a little bit ago, we were talking about like keeping the turbine from melting? You can just run it off of, like off nominal, basically off, you know, typically fuel rich, just run more fuel through that so it's cool enough. You can actually do that locally, kind of in your engine so that you can keep it so, you know, imagine a combustion chamber and The top of it's just a flat, like imagine a shower head and then you have like, you know, the combustion chamber attached to it. The outer perimeter there, the, the part where the flame front would be touching the walls, you can actually have just more fuel injectors. So you're injecting locally of more fuel-rich zone along the entire nozzle. And that would be called film cooling. So it's, it's less efficient though. Again, you're kind of wasting fuel.

• 1:35:52Speaker 01

  There's fuel that's running, you know, and your, your, your mixture ratio is off, but only for a little portion of your, the big picture, you know? So that's one of those compromises. Like you can do additional film cooling to make sure you're not melting your engine, you know, but at the cost of performance usually. But you can also be smart and use film cooling. You know, there's fun little clever tricks. For instance, you'll notice on the F1 engine that was on the Saturn V, you know, the biggest rocket that had been built to date prior now to a starship.

• 1:36:24Speaker 01

  The F1 has this huge, huge, huge engines. There's five of them on Saturn V. And you'll notice that like the, the gas generator has a pipe that comes down. And then it actually splits off in a manifold and wraps around part of the nozzle. And that manifold takes the hot gas from the turbine, which, which is actually, I mean, it's not hot. It's actually cold gas compared to the combustion chamber. But it's, you know, in human terms, it's still, you wouldn't want to put your hand in it. You know, not live. And it actually pipes that gas into the nozzle so that it creates a film cooling, of, of, an actual boundary layer of cooler gas against the hotter combustion chamber gas.

• 1:37:06Speaker 01

  So basically repurposing that gas that was normally wasted and they pump it back into the engine. And then into the nozzle, like kind of further down. So the, the trick there is it has to be far enough down that the pressure at the, in the nozzle, because remember as the nozzle gets bigger and bigger and bigger, the pressure is getting lower and lower and the temperature is getting lower and lower. So you have to find this trade-off point where the pressure is. Is lower than that gas from the turbine. And then you pump it in and it's cooler than the than the gas still is in the nozzle. And it can help not melt your nozzle. So you'll notice that the F1 is actually a good example of regen cooling. So the chamber walls, you can physically see the pipes actually on the F1 because it's so big. And they just literally used pipes and bent them.

• 1:37:48Speaker 01

  And you can see the coolant channels all the way up and down the engine until you get to that manifold. Then from there on, it just has what's called a nozzle extension and it keeps going and going and going. And that section of nozzle is cooled by the film cooling of the gas generator.

• 1:38:04Lex Fridman?

  I mean, the aerodynamics of cooler gas and the hot gas. Because you have to have this kind of layer, right? To protect a layer of cool, like understanding that obviously probably has to do in modern times. There's probably really good simulation of aerodynamics. But and to do it in terms of pressure too, like to make sure it's in the right place.

• 1:38:27Speaker 01

  Yeah.

• 1:38:28Lex Fridman?

  That doesn't like go back up.

• 1:38:29Speaker 01

  Go backwards. Exactly. If they have that manifold, even six inches too high on that nozzle. Yeah, it's just going to go upwards, you know? Pressure always wants to flow from high to low.

• 1:38:39Lex Fridman?

  The number of options you have here that result in it going boom is very large.

• 1:38:45Speaker 01

  Near infinity. Yeah.

• 1:38:47Lex Fridman?

  Especially because, I mean, you can't do like a small model of it. Maybe you can. No, you can't.

• 1:38:52Speaker 01

  It doesn't really scale very well.

• 1:38:53Lex Fridman?

  No, you have to do the full testing. And that's why you have all the kind of that's. That's why you have with Starship, all the tests that, you know? You think, why would you need to do so many static fires and so many tests? And why is it failing so many times? Can't you get it right? But like, it's very tough to get it right.

• 1:39:12Speaker 01

  Well, and when you're pushing the boundaries, you want to know where and how it's going to fail.

• 1:39:17Lex Fridman?

  That's right.

• 1:39:17Speaker 01

  So you can engineer around them. So that's, that's a luxury that SpaceX does have with the scale of Raptor. You know, they're building Raptor cheaper than probably almost any other engine. You know, maybe besides some of their own, at least at that scale. Then before they're testing, you know, I think since last March or last April. They've tested a thousand Raptor, you know, a thousand engine fires, I guess, not just Raptors. But, you know, that's just an insane amount of data and an insane amount of edge cases to learn. Oh, my God, we found out that we were actually slightly over spinning our turbine at this degree. And this frequency is harmonic at this blah, blah, blah. And all of a sudden realize it's rattling and, you know, it did this. And then you can engineer around that, you know, it's like.

• 1:39:56Speaker 01

  Ultimately, you know, I think Elon said something like, high production rate solves many ills, or something along those lines. And it's just true. If you have an insane amount of engines, and an insane amount of data, and insane amount of failures to learn from, you just know your system inside out. You know those margins, you know where the failure points are, you know how to engineer around them. And

• 1:40:18Lex Fridman?

  That's how I approached dating. No, I'm just kidding. Because we're talking about engines. So most rockets, I think all rockets have multiple stages today. Maybe they'll take us in a discussion of what ideas that could be for single-stage to orbit rockets. But can you describe this whole thing that you've been mentioning here and there of multiple stages of a rocket?

• 1:40:40Speaker 01

  Yeah, no, that's a good question. So ultimately, you know, like I said, you're kind of pushing about 90% of rockets, like basically just fuel with some skin on it. You know what I mean? And so that skin weighs a lot of, you know, skin and the engines do weigh a lot. You know, like I said, the Falcon 9 on its own is about 20 tons. Just the booster is about 20 metric tons. So it's not an insignificant amount of weight. So the idea is with staging is you ditch anything you don't need, more or less. So in the, you know, Falcon 9 is a perfect rocket to think about this because you have an upper stage, and you have a booster, you know, or first stage. And the first stage burns through all its fuel. Once it's out of fuel, you let go of the second stage and ta-da, you actually

• 1:41:23Speaker 01

  just basically started and lit a brand new, fresh rocket. You know, this brand new, fresh rocket now doesn't have all that, that 20 tons attached to it. So it's a lot lighter. It doesn't need, you know, as nearly as many engines to push it around. It needs just one instead of nine. Its engine can be optimized for the vacuum of space as opposed to having to operate at sea level with all of our, actually pretty thick atmosphere, you know, relatively. So there's, so staging is basically the idea that you get rid of things you don't need. On Earth, again, kind of that whole like 10% harder, 10% easier. If it was 10% easier, single-stage orbit would be no big deal. And it probably would have been like the, the way to get to orbit by choice, just because like, it's not that hard. But with

• 1:42:08Speaker 01

  our Earth as it is, with physics as it is, it's just It's doable and we've had, and you know, we almost kind of actually the first orbit to take humans or the first rocket to take humans into orbit for from the United States, which was the Atlas rocket was kind of a stage and a half. It actually only had like one big fuel tank. And what that is, they actually dropped off two of its three engines. So it just ditched some of the engines. But if it hadn't done that, you know, so kind of people were like, well, that was single stage. It's like, it still had a staging event. It still had a ditch mass in order to even make it into orbit. Had it not done that, it would have not been able to get into orbit. So you pretty quickly look at your trade and say, okay, well, if I want to stick to single stage to orbit, my payload

• 1:42:52Speaker 01

  mass becomes tiny, you know, like you might be able to put like, you know, a Falcon 9 booster on its own. Like if you just flew one of the side core boosters of a Falcon Heavy with a nose cone on and everything to say, I'm just going to fly this on its own. You might be able to put like, you know, 10 kilograms into space or something, you know, a very small amount. Well, throw a second stage on that thing. And now you can put, you know, 17,000 kilograms into space. So it's just an order, you know, orders of magnitude more payload capacity because you did staging, because you ditched the residual weight. So the other thing that's hard about that too, is that the engines, again, that

• 1:43:34Speaker 01

  operate at sea level are often not great in space and vice versa. Like you physically can't most optimized for space engines, you can't even operate at sea level. They'll destroy themselves due to something called flow separation. So not only are you getting the benefit of ditching all the weight, but you're also able to use a much more efficient and less typically, you know, much less powerful engine in space.

• 1:43:57Lex Fridman?

  So you mentioned on the multi-stage rockets, that maybe the dream would be if we weren't living on Earth, but maybe we can on Earth to have a single stage to orbit rocket where it's all one package reusable.

• 1:44:14Speaker 01

  Mm hmm. Reusable gets even harder.

• 1:44:17Lex Fridman?

  It gets even harder. So first of all, what is, just to linger on it, what is the single stage to orbit rocket? And why is it so hard to achieve on Earth? You already kind of explained it a little bit, but just if we were to say like, that's your assignment.

• 1:44:32Speaker 01

  Yeah.

• 1:44:32Lex Fridman?

  Tim, you're supposed to get together with Elon and other brilliant people and like you have to do this.

• 1:44:38Speaker 01

  Yeah.

• 1:44:39Lex Fridman?

  Why is it so hard?

• 1:44:41Speaker 01

  Why is it so hard? It, your, the, the payload fraction of a rocket is like three to five or six or seven percent would be like, you know, that's the amount of payload compared to the total mass of the rocket. Like you're lucky to get into beyond 5%. So if you're now having to deal with the weight of the rocket, by the time you're in orbit, like your, your payload fraction, just, you're, you're talking about like margins, it's such, it's so small amount of leftover. If you have to take all of it with you. So the sooner you can ditch weight, the better. The sooner you can ditch weight, the better. The sooner you can, you know, and that's what you're doing. A rocket the whole time is actually ditching weight.

• 1:45:22Speaker 01

  All of that fuel and all that big giant flame you see is literally mass being thrown out the back of the rocket. But what typically isn't expended, you know, at least during nominal operations, you're not seeing the engines being, you know, expelled out the thing. Until you get to staging, of course. And that's where, you know, you're ditching all that dead weight. So a single stage to orbit, your margins just become so small that it, it's border, it's not impossible. But it's just, at the end of the day, like almost no matter who you are, you end up saying it's just simply not worth it. Like it'd be, if you have two rockets that are using the same amount of propellant, you know, they're the same physical sizes and one of them is cutting, you know, on a third and has another little engine. It'll have a hundred or a thousand times more payload capacity than the one sitting right next to it.

• 1:46:05Speaker 01

  And now, so there's tricks you can do to like, try to offset that. Things like aerospike engines, which operate at, as efficiently at sea level, at kind of optimized efficiency at sea level. And just by their, by the way, their design, the physics of them, they're also efficient in a vacuum too. You can do the things like that. And at the end of the day though, you just end up with a worse rocket than if you had just done staged, like no matter what. And, and people say like, well, what if you would develop the new technologies? Like, okay, well, apply that technology to a multi-stage rocket. And it's gonna do better, you know, like no matter where you end up, it's just always better to ditch that weight, you know?

• 1:46:42Lex Fridman?

  Is there a cost to having multi-stage? Cause you can still reuse the different stages?

• 1:46:47Speaker 01

  That's the, the dream is, you know, becomes easier to reuse multiple stages because now, you know, like the booster doesn't have to survive orbital reentry temperatures and extreme environments. And you only have to, you know, make survivable the upper stage. You only have to put a big heat shield. I mean, Starship's the perfect, perfect thing of this. The, the upper stage has a big giant heat shield. The booster doesn't need it because it's not going, the booster's not going to orbit. It's only going a fifth or a quarter of orbital velocity. So it's heat that it experiences is survivable just by the stainless steel. You don't need an additional heat shield. So all of a sudden, if you're trying to reuse, pretend that you just welded the two stages of Starship together, remove those engines on Starship, that whole vehicle, if you're trying to reuse it, the whole vehicle now has to have a heat shield on one side of it.

• 1:47:31Speaker 01

  The whole thing has to have these big, heavy wings. By the time you come down to it, there's probably just zero payload capacity. You basically put your fuel tank in space, you know? Good job.

• 1:47:40Lex Fridman?

  So the, the dream of a single stage to orbit a rocket, is, is that just even the wrong dream on earth?

• 1:47:49Speaker 01

  That's what most convention tells you, you know? By the time, if, if you're, you're, if your goal is cheap, then you're going to spend, you're going to have a physically larger rocket that has more engines, that has more propellant, blah, blah, blah, to put the same amount of thing, same amount of mass into orbit compared to something else. You know, we're talking like Rocket Labs Electron, a really small rocket. It's like, I think 1.3 meters wide and something like, you know, 18 meters tall or something. It's, it's, it's a small rocket. If you were to, you know, the, and it can put something like 300 and or so kilograms into orbit. You could either launch something that size or again, like a full, like big old Falcon 9 booster, the huge, huge thing. And that would be lucky to put 300 kilograms into orbit, you know?

• 1:48:34Speaker 01

  So it's like, which one's going to be cheaper to build, you know, ship around all the stuff? And then you also look at, you have fixed costs, like. The idea of flying a, but this, this, again, everything in rocket science is a compromise because now you have things like people on console time, all the people that are, you know, on comms and working on the rocket, going down to the pad, you know, filing paperwork, doing range control, making sure there's not planes and boats in the way, flight termination. You have all these fixed costs for any launch. I don't care how big the rocket is, there's a relatively fixed cost. So now you say like, okay, I'm going to be paying, well, let's just make it one of them. I'm going to pay $5 million to fly a rocket between all the people going on site, all the propellant, all the licenses, blah, blah, blah. If your

• 1:49:19Speaker 01

  fixed cost is $5 million, you can put 300 kilograms in space versus you have a $5 million cost of operation and you can put 5,000 kilograms into space, like it's, the business case is going to send you in one direction pretty quickly.

• 1:49:33Lex Fridman?

  So you mentioned aerospike engines. I think the internet informed me of your love affair with aerospike engines. Find somebody that looks at you the way Tim now looks at aerospike engines. Can you explain what these are? How do they work? What's beautiful to them? How practical are they? Why don't we use them?

• 1:49:58Speaker 01

  Oh my God.

• 1:49:59Lex Fridman?

  Does it just boil down to the design of the nozzle? So maybe can you explain how is it possible to achieve this thing for an engine to be as efficient at, in a vacuum and sea level and in all different conditions?

• 1:50:11Speaker 01

  You know what I love about this is that every question you've asked me is like a one hour video on my YouTube channel. I was like, now boil it down to 45 seconds. So the aerospike engine basically is an inside out engine, more or less. So with a traditional engine, you know, we've talked about the combustion chamber and the throat, and then it expands out into the nozzle. Those walls are containing the pressure, right? An aerospike is the opposite. It's basically the pressure of the engine is on the outside of it and it's pushing inward against a spike. So it's, it's almost like, it's like, like the difference of if you were, let me think about this. If you were standing in like a, a tent or a teepee, right? And you put your arms at the top and you pushed your arms out,

• 1:50:55Speaker 01

  like into an iron cross or something, you know, you can physically lift the tent just by pushing outwards on the tent walls, right? Well, that would be like a traditional nozzle. Now aerospike would be almost like squeezing an ice cube. And if you squeeze an ice cube, you can push in on it and kind of that wedge force will shoot that ice cube. So that's kind of what has happened. We have the high pressure gases on the outside of the spike squeezing in on that spike and that's, and then it's pushing up against the, you know, because it's equal on both sides against the, kind of the ramp is pushing up against the rocket. So that's where that force comes in is against the nozzle, against the chambers. The hard part with an aerospike. So the cool, okay, I guess the cool thing about an aerospike is that it can operate in space. You can have what's

• 1:51:38Speaker 01

  known as a really big expansion ratio. So that's your ratio between the throat, the area of the throat versus the area of the nozzle exit. And remember how the bigger the nozzle is, the, it's continually just converting more and more is converting that high energy, hot, high pressure gas into cooler and cooler, lower pressure and faster gas. So each little millimeter along that nozzle is just getting it lower pressure and cooler, but faster. Now, if you take a big nozzle on earth and you, at sea level, and you fire it, you can actually get, even though we're going from, say, 300 bar, the Raptor engine, you know, our atmosphere at sea level is about one bar. It's pretty much exactly one bar, depending on conditions. But you can actually

• 1:52:22Speaker 01

  get a nozzle to get way below one bar of pressure. So every little, you know, you can go from 300 bar in just two meters down to one bar or below one bar. There's actually a limit. You can actually only expand it below, you know, we'll say something like 70%. So you can get down to like 0.7 bar at nozzle exit before the pressure of the atmosphere is actually squeezing in on that exhaust and tearing it away from the walls of the engine, the walls of the nozzle exit. And what happens is it's, it's kind of unpredictable. You get these pockets, these oscillations, and they'll be so extreme that they'll end up just destroying the nozzle. So you can't lower, you can't have a bigger expansion ratio than again, relatively speaking,

• 1:53:07Speaker 01

  something like point seven, like you can't go below, you can't get that pressure exit too much below ambient air pressure before flow separation can destroy the engine.

• 1:53:16Lex Fridman?

  So how come this engine can do so well in, in, in different pressure conditions?

• 1:53:21Speaker 01

  So because it's inside out, the ambient pressure is pushing the exhaust gas into the wall as opposed to a conventional engine that exhaust gas, the ambient air is actually squeezing the exhaust gas away from the walls of the engine. And that squeezing away from is what can be destructive. So that since the instance is kind of inside out, the ambient air is pushing the exhaust gas into the engine walls. So you can't have flow separation. You won't have flow separation. Now what happens is so you can have this huge amazingly like efficient vacuum engine that's, that has a, we'll say a 200 to one expansion ratio, which is really big. Like a lot of sea level engines are like 35, 40, 50 to one expansion ratios. And then

• 1:54:03Speaker 01

  in space, you know, it's common to use like 150, 180, 200 to one expansion ratios. So an aerospike can have something like 200 to one. It's just that the, at sea level, it's kind of just getting pushed and it's kind of getting cut off early almost, but it doesn't matter. It's not like destructive. It's just not running at its maximum efficiency. As it climbs in altitude, as the ambient air gets thinner and thinner and thinner, it just inherently is pushing less and less and less against the walls of that aerospike engine. So it actually continually gets more efficient at, you know, as it climbs in altitude, as, as does a normal engine, but the difference is that you can use that huge expansion ratio at sea level and you can't use a huge expansion ratio at sea level with a traditional, traditional nozzle.

• 1:54:46Lex Fridman?

  Has anyone actually flown an aerospike engine?

• 1:54:49Speaker 01

  No aerospike engine to date has ever been flown on an orbital rocket.

• 1:54:52Lex Fridman?

  Why not? And would you like to see a future where they're used?

• 1:54:56Speaker 01

  Purely, purely because I think they're cool.

• 1:54:59Lex Fridman?

  Yeah.

• 1:54:59Speaker 01

  You know, in the same way.

• 1:55:00Lex Fridman?

  That's the core of your love affair with air spike engines.

• 1:55:02Speaker 01

  It's just, and I said this in my video, actually, they're outside before I came in here, I saw an RX7 in the streets that I just love, and that uses a rotary engine. On paper, the rotary engine is like more efficient, does all, you know, smaller, more efficient, all these things. But in practice, it's like, the thing is actually just like unreliable, hot, and it, you know, it blah, blah, blah, blah. Burns oil. It's kind of the same thing with the air spike engine. Like, yes, on paper, it's more efficient, but now you have a lot more surface area of your, your, your, your throat area, no matter what is going to have, the throat of the rocket engine is always where it's the hottest. You know, it's the hardest thing to cool.

• 1:55:41Speaker 01

  And with an air spike, if, you know, if it's inside out, now your throat is, no matter what, like way bigger. You know, it's almost like the size of the nozzle exit normally, but now it's your hardest thing to cool and you have a ton of it. And you also have two edges of it, no matter what. So even if you have like a, you know, a circle inside a circle, you have like a just insane amount more surface area to cool with a limited amount of fuel. Don't forget, you're using your fuel as your, as your coolant. So if you all of a sudden now take your throat area and you have X amount of space that you need to cool, you only have, you have a limited supply. It's like, oh, it's, sorry, this is the stuff that just.

• 1:56:21Lex Fridman?

  Are there ideas of for cooling, of for cooling air spike engines?

• 1:56:26Speaker 01

  It's same physics apply for an air spike as they would. So you just run into, you just run into a limitation. Like at some point, I'm not flowing enough propellant. My, it scales, it scales kind of poorly. You know what I mean? Like, you can increase the thrust of an air spike by making it bigger and increase the mass flow and the fuel going through the throats or the throat, but at the same time, like it just, it's, at the end of the day, it's physically possible. It's a lot more complex. You have a lot of issues with cooling and it just, you end up kind of right back where you started. So it's like, is it worth it to just keep going down this rabbit hole? You're trying to engineer this thing to work when like you could have probably spent a tenth the amount of time just slightly increasing the performance of your normal engine in the first place, you know?

• 1:57:09Lex Fridman?

  Again, I'm going to anthropomorphize that lesson and apply it to my dating life. And once again, just kidding. Okay. Actually, just on a small tangent, since you are also a car guy, what's the greatest combustion engine car ever made to you? If you had to pick something, what's the coolest, the sexiest, the most powerful, the classiest, the most elegant, well-designed? I don't know what.

• 1:57:38Speaker 01

  A lot of those things are different for me, but I'd say I still, it's funny because now, maybe it's just because it's fresh on mind, but I love that mid 90s RX 7, which, you know, especially in Japan, they had the 20B, a tri-rotor. That is like the coolest engine ever to me.

• 1:57:59Speaker 01

  The FD RX 7. It's just too darn cool, honestly.

• 1:58:05Speaker 01

  It'd be, there you go.

• 1:58:08Lex Fridman?

  Well, what about the mid 90s that makes it special?

• 1:58:11Speaker 01

  Just that's the only time.

• 1:58:11Lex Fridman?

  Everything was.

• 1:58:12Speaker 01

  It's more that I love the engine and I like the car it's attached to. And I'm not actually a big fan of like 90s styling, you know, personally. But just that the 20B is just such a cool, cool engine. And it's twin-turbo sequential turbos. They used, they, a bigger turbo takes longer to spool up. You know, it takes more, it's using that same like a turbine and a compressor. And it just, if it's a large turbine, it takes more exhaust gas to get it spooled up. So if you have an engine that revs to 9,000 RPM and you want to get a lot of pressure out of that turbo, you have a big turbo, it's going to take forever. Like you're going to have, you know, your floor and then like, it's going to take a long time for that turbo to get spooled up. So they actually did a small turbo on it and a big turbo. So the small turbo would spool up first, get some boost going through the engine, get that engine operating,

• 1:58:57Speaker 01

  get it up to speed, get it, you know, get some power to the wheels. And then once that kind of reaches its limit, you'd flow it into the, divert the exhaust gas into the bigger turbo. It's this sequential turbo. And then that now can supplement and actually increase the, you know, overall performance of the vehicle by a lot. And I just, I think that's just so cool. It's, it's just like the ultimate like brute force, out of the box thinking. And it actually made it into production. You know what I mean?

• 1:59:22Lex Fridman?

  Can you, what's the sound like? Can you tell an engine by its sound?

• 1:59:27Speaker 01

  It sounds like a really, really, really angry lawnmower.

• 1:59:32Speaker 01

  It sounds horrible. It's actually a terrible sounding car. In my opinion, like it sounds just raspy and like the opposite of like a big muscle car. You know, like a big muscle car is this deep gutter roll like, oh, it just hits you. This is like, it's just gonna annoy the hell out of you and all your neighbors. Like it's.

• 1:59:48Lex Fridman?

  But you love the engineering.

• 1:59:49Speaker 01

  I love the engineering of it.

• 1:59:50Lex Fridman?

  So to you, the car is the engine. It's not all the surface stuff, all the design stuff, all the, you know, yeah, the elegance, the curves, whatever it is.

• 2:00:02Speaker 01

  Well, those come and go, you know, to me, styles change.

• 2:00:05Lex Fridman?

  Forever.

• 2:00:06Speaker 01

  Yeah.

• 2:00:07Lex Fridman?

  I'm gonna apply that to my dating life once again. The metaphors just keep on coming.

• 2:00:12Speaker 01

  Well, if you think about it, like my tastes has changed throughout the years. When I first saw a Model 3 Tesla, I thought it was the most hideous car ever. Without the gorillas, like this is so stupid. It took me all but two months to think that it is one of the coolest looking cars. Same with Cybertruck. I mourned Cybertruck. When I first saw that thing, I was at that that thing with, and I went with, we used to do a podcast called Our Ludicrous Future. So we talked a lot about like, you know, cars and EVs and stuff. We went to that unveiling and literally like, we had like almost a non-alcohol induced hangover the next morning of like mourning the hideousness of Cybertruck. Come six months later, a year later, and I'm like, damn it, that thing's actually kind of cool.

• 2:00:53Lex Fridman?

  Yeah. That also teaches you something about, again, it's the thing you said earlier, sort of going against the current or the experts or the beliefs or whatever is and making a decision from first principles. Some of that also applies to design and styling and fashion and culture and all of that. Some of that, you know, so in fashion especially, it's so interesting.

• 2:01:17Speaker 01

  So subjective.

• 2:01:18Lex Fridman?

  Being rebellious against the current, the current fads actually is the way to pave.

• 2:01:27Lex Fridman?

  The new fads.

• 2:01:28Speaker 01

  Well, it didn't take long for others to follow. You look at like currently like what Hyundai's doing with their, I forget which one, like the Ioniq or something like that. It's, it's square. It's like, it's boxy. You know, it's, it's a throwback. It's eighties. It's got these beautiful retro taillights. It's got these square headlights. It's, it's, it's very inspired by Cybertruck, in my opinion. I mean, it might not be. It might be coincidental that we're all kind of getting this retro future vibe, but.

• 2:01:54Lex Fridman?

  Uh, I personally like the boxy. So I never, I still haven't understood, uh, Porsches. Porsches. I still can't quite understand the small size, the elegant, the curves. I don't quite, I don't quite get it.

• 2:02:11Speaker 01

  Like I said, I don't love the look of the RX seven. I don't love it, but I love it because of the engineering, I guess, that it represents. You know what I mean?

• 2:02:19Lex Fridman?

  Yeah, it's, it's, uh, it's not the surface stuff. It's the deep down stuff.

• 2:02:24Speaker 01

  It's that 50 50 weight distribution that matters.

• 2:02:27Lex Fridman?

  All right, let's, uh, let's talk about Starship a little bit. We've been sneaking up to it from a bunch of different directions. Can you just say, um, what is Starship and what is the most impressive thing to you about it? I mean, you've talked about the sort of the engines involved. Maybe you haven't really kind of like dancing around it, but because this is such a crucial thing in terms of the next few years, in terms of your own life personally, and also just human civilization reaching out to the stars. It seems like Starship is a really important vehicle to making that happen. So what is this thing that we're talking about?

• 2:03:08Speaker 01

  Yeah. So Starship is, uh, currently in development, the world's largest, most powerful rocket ever built, fully reusable rocket, a two-stage rocket. So the booster is landed and, you know, all this is currently aspirational until it's working. Uh, so I'll, I'll, I'll say it's, I'll say what it's aspirationally going to be. And obviously I have faith that that will happen, but just factually. So the, the booster will be reused, landed and refueled and reused. Upper stage will be landed, refueled and reused and ideally rapidly in the in the sense not talking about months or weeks of refurbishment, but literally talking about like mild inspections and ideally like under 24 hour reuse, you know, where you literally land it and fly it like an airplane.

• 2:03:54Speaker 01

  So it utilizes liquid methane and liquid oxygen as its as its propellants. It utilizes the current iterations of it are 33 Raptor engines on the booster engine on the booster and six Raptors on the second stage. So there'll be three that are vacuum optimized and three that are sea level optimized on the upper stage that are primarily they'll be used, I think, at stage separation anyway in space, but they'll their main reason that they use them is so they can use them for landing to the the three sea level engines to be able to propulsively land the upper stage as well.

• 2:04:29Lex Fridman?

  So the three Raptor engines are the ones that generate the thrust that makes it the most powerful rocket ever built.

• 2:04:35Speaker 01

  By almost double.

• 2:04:38Lex Fridman?

  Compared to the Saturn five, really?

• 2:04:40Speaker 01

  The N one had 45 mega newtons of thrust. The Saturn five had, I think, 35 or 40 mega newtons of thrust. And this has 75 mega newtons. So we're talking almost double.

• 2:04:54Speaker 01

  It's a it's a lot of power.

• 2:04:59Lex Fridman?

  That could be the sexiest thing I've ever heard. Okay.

• 2:05:02Lex Fridman?

  So so what are the different testing that's happening? So like, uh, what's a static fire with some of these Raptors look like and where do we stand? You were you're just talking about offline like the thing that happened yesterday.

• 2:05:15Speaker 01

  Yeah.

• 2:05:15Lex Fridman?

  It was impressive.

• 2:05:16Speaker 01

  You know, everything in this is kind of iterations. And so, you know, the the milestones that we're seeing, we actually have on everydayastronaut.com. We have a milestone checklist of like all the things we're hoping to see that we kind of need to see before the first orbital flight of this rocket. So a big milestone that got checked off yesterday was a wet dress rehearsal. So it's literally like fueling the rocket up. Getting ready to do everything but lighting the engines, basically. So we're talking about loading it with propellant all the way. This is the first time, yep, right there.

• 2:05:45Lex Fridman?

  Where's the milestones?

• 2:05:46Speaker 01

  Right there at the top. Click that big picture. Yep, just anywhere, that big picture. Yep.

• 2:05:52Lex Fridman?

  So there's the wet dress rehearsal. So what's the wet dress rehearsal?

• 2:05:55Speaker 01

  Yep. So that's where they, for the first time, they filled it completely to the brim with both liquid oxygen and liquid methane. Now, they had done component level testing where they fill it with liquid nitrogen, which is, you know, it's an inert gas. So it's not like, say it leaks out, it's not going to explode. You could just have a big giant pool of liquid nitrogen, like flooding the area, but it's not going to be an explosion. So they've done that for cryo testing to make sure all the components and stuff can handle, you know, being at cryogenic temperatures. It's kind of a good analog before you start putting your fuel and your oxidizer in there. But now, as of yesterday, they fully fueled the rocket with propellant, both stages, the first stage and the second stage, while fully stacked on the pad, like basically, I mean, it's the first sense

• 2:06:38Speaker 01

  we really got of like, this is what it's going to look like right before it takes off. You know, kind of breathing, coming into life for the first time.

• 2:06:45Lex Fridman?

  What does the pad look like? So there's a few interesting aspects of this. What's up with the chopsticks and all of that?

• 2:06:52Speaker 01

  Yeah. So the launch pad is unique. I've never seen anything like it in the prior history of spaceflight. But it's a really simple launch stand. They basically have like this, almost looks like a stool, like a, you know, like a milking a cow stool thing with a whole, a big giant.

• 2:07:10Lex Fridman?

  Now, I know you're from Iowa, but yeah.

• 2:07:13Lex Fridman?

  Yes, we all know what that stool looks like.

• 2:07:15Speaker 01

  We all been sitting on that stool milking cows.

• 2:07:17Lex Fridman?

  Yeah.

• 2:07:20Speaker 01

  With a giant hole in the middle, and that hole in the middle of that stool is where the rocket sits. And it sits on these, you know, launch clamps. And then next to it is the, so that's the orbital launch mount. And then next to it, they are the OLM, some people will say. Next to it is the orbital launch tower, the OLT. And that is not only integral to fueling up the upper stage, you know, the upper stage has to have propellant lines run to it so that they can fill it with propellant and, you know, all that. But it also, they ended up making it so instead of having a big crane on site to stack the two on top of each other, they literally just use that tower as a crane. So the crane has these giant arms, lovingly called the chopsticks, or the whole system can be called Mechazilla.

• 2:08:02Speaker 01

  And that will grab on to first it'll grab on to the booster, pick it up off of its off of its transporter that transports it from the production site. Lift it up, puts it down onto the launch mount and then it will pick up the second stage or the upper stage starship. And plop it down on top of the booster. And they did that for the first time last year. Actually, I think it was like Valentine's last year was the first time they used the chopsticks to stack it. And now they're doing it quite frequently, you know, but ultimately those chopsticks have to serve a second purpose. They're actually going to utilize, if you say catch the, it's not so much they're going to catch the booster with these chopsticks. It's not like it's, you know, a dad trying to catch a falling child, you know? It's more that the, the booster and the starship will someday land on those arms.

• 2:08:47Lex Fridman?

  Yeah.

• 2:08:48Speaker 01

  So they're more or less stationary. I'm sure there's some bit of, you know, adjustment that the arms will do, but more or less the rocket's going to propulsively land. And get picked up by like, what's essentially like two, like relatively small ball joints that hold the entire thing. It's, it has to land very precisely on these, these mounts and on, onto the, the launch mount. And then that's what's going to just place it back onto the stand and allow it to be refueled and fly again.

• 2:09:16Lex Fridman?

  What's the idea of using the arms versus having a launch pad to land on? What's, what's the benefit?

• 2:09:22Speaker 01

  You are basically removing the mass of what would be heavy landing legs. And you're putting kind of that landing infrastructure onto a ground system. So you're not having to carry those landing legs into orbit.

• 2:09:33Lex Fridman?

  But it's, it's also elevated off the ground. Is there some aspect to that where you don't have to balance the thrust and all the?

• 2:09:39Speaker 01

  You, you, you can negate some of those, like, there's like plume, plume interactions. There's like, you know, the exhaust hitting concrete. And especially with a rocket this big, it's going to, you know, use like three raptor engines firing. If, you know, if you have them firing really close to the ground, you're just going to absolutely destroy and crater the ground. And you're going to refurbish the, the ground and the, the landing pad every time. And you know, or have huge landing legs that are super long and tall, you know, to make it so it's elevated enough to not do that. So yeah, you're kind of, you're avoiding that whole mess by catching it high enough off the ground that you don't have to factor that in.

• 2:10:13Lex Fridman?

  And that's how many engines are involved in the landing part? Is it three raptor engines?

• 2:10:17Speaker 01

  Well, we haven't actually, you know, we haven't to date seen the exact landing sequence. So it might be something like at first they might light up, you know, seven or something or nine or something, some number to accelerate quickly or decelerate quickly, same thing. And, and then shut it down to three or something for a little bit more granular control. Cause unlike Falcon nine, Starship has enough engines and variability to actually, if it needed to hover, you know, to maybe more precisely align itself with the pad, it would have that capability. And especially having multiple engines, you know, if you only have a single engine running, you can't really roll. You know, your roll axis, you can do pitch and yaw because the, the engine is kind of like a rudder. It, it can move in two axes.

• 2:11:00Speaker 01

  So you can easily pitch and yaw the vehicle, but to actually induce roll along its, its vertical axis, you, you would either need like auxiliary engines to roll it, or you'd need a pair of engines so they can be opposed and induce roll. So by having two or three running, they have all three axes of control that they would need, kind of like a broomstick, you know, and balancing a broomstick on your hand. They can just move it over. And if they need to align it to those landing nubs, you know, on the landing arms and stuff like that, then they can do that.

• 2:11:29Lex Fridman?

  Uh, speaking of pitch and yaw, the thing, uh, so Starship flips and it's belly flops. There's a interesting kind of maneuver on the way down to land. Uh, can you describe that maneuver? What's involved with that?

• 2:11:44Speaker 01

  Yeah. So this is definitely a first. I don't think anything's tried landing like this before, but the idea is when you're falling through the atmosphere, the atmosphere could actually do a lot of work for you. You know, you're moving quickly. Something is falling from space. There's a lot of energy involved.

• 2:11:59Lex Fridman?

  You have a really good video on this as well?

• 2:12:02Speaker 01

  And uh, thank you. Um, the uh, as it's falling, you know, you can, you let the, you want to let the atmosphere do as much work as it can. And so um, if you have a uh, unsymmetric, you know, it's not a ball that's falling. This is some kind of object with, with shape. Some, you know, at, at one face of it is going to have more surface area than the other face. So, you know, in the, in the shape of like a cylinder, if you're falling, you know, like a soda can, if you're falling top or bottom first, it's a certain amount of surface area. If you flip that on its side, you actually have a lot more surface area. So with the same exact vehicle, you can actually have a lot more drag. You can actually slow it down a lot more using the exact same like, same atmosphere, same, same vehicle, just by turning it 90 degrees,

• 2:12:47Speaker 01

  you can slow it down substantially, like three or four times slower. So that's energy that you don't have to use anywhere else. You know, you don't have to use an engine to slow you down. You don't have to do anything else. So SpaceX realized, okay, if we flip this thing on its side and let it fall like a skydiver almost, you know, instead of like pencil diving into the pool, you're belly flopping. You're maximizing the amount of surface area that's in the wind stream that's being slowed down. But obviously, like, in order to land, especially if you're SpaceX and, you know, Elon's obsessed with like not having different parts, you know, he wants, the best part is no part. So if you're going to land with the engines, you might as well use engines that you've already have, the, the engines that are, you know, used for the other portions of flight. So you kick those

• 2:13:30Speaker 01

  on and you use those engines to actually turn it 90 degrees from belly flopping to feet first. And that way you can use those same engines to land and you don't have to have like auxiliary landing engines. You don't have to have forces, you know, even if you were to land like on its belly with a separate set of engines. Not only would those engines weigh a lot, you know, and be extra complexity, et cetera, et cetera, but you also don't have to make the ship be able to handle landing, you know, like on its belly as opposed to having the forces be vertical through it.

• 2:13:58Lex Fridman?

  But it's a giant thing. You have to rotate in the air.

• 2:14:03Speaker 01

  Huge.

• 2:14:04Lex Fridman?

  And uh, as you also highlight, you know, there's liquid fuel slushing around in the tank. So like, you can't uh, I guess, use that fuel directly. You have to have another kind of fuel. Like, there's just complexities there.

• 2:14:18Speaker 01

  Yeah.

• 2:14:18Lex Fridman?

  That are involved. Uh, plus, the actual maneuver. It's difficult from the like, like, what are the thrusts that actually make that make all that happen? You're adding a lot of complexity, not a lot, but your complexity to the maneuver and possibility where failure could happen in order to sort of save, in order for the air to do some of the work. So what is some of that complexity? Just you can linger on it?

• 2:14:48Speaker 01

  You know, if you if you think about what it's going to take to go from horizontal to vertical, this rocket in particular, Starship, has these big flaps. So it has kind of two nose flaps and two rearward flaps. The rearward flaps are a lot bigger because the majority of the mass, the engines and stuff are in the back of the vehicle. So in order to kind of be stable, and they just fold themselves inwards, like on their dihedral angle, at a dihedral angle, in order to increase or decrease the drag. So you can control its all three axes of control while it's falling, you know, on its belly, you can control it that way using these four different fins. So you have these giant moving surfaces that take thousands of horsepower, it's just insane amount of torque in order to move these quickly

• 2:15:33Speaker 01

  enough to be a valid control surface. So that's a huge complication of moving these fins and developing that that landing algorithm and the, you know, the control for a huge vehicle with flaps going like, you know, in and out, in and out, in and out to stay stable. Then, right as you light the engines, now all of a sudden, you want the top, you know, you want to flip the rocket 90 degrees. So the rearward flaps, the bottom flaps fold in, they tuck all the way in to minimize drag. That's going to make it want to, you know, swing down. You extend the upper flaps, that makes it so the nose wants it to pitch up. You kick on the engines. They're now lighting all three engines, at least as of the last, like, successful attempts. They light all three of the sea level raptor engines and they're pitched all the way, like, you know, 10 or 15 degrees or whatever the maximum

• 2:16:16Speaker 01

  pitch is on them. And that induces, you know, it does that kick maneuver to kick it over from horizontal to vertical. Now, the problem is you lit your engines while you're horizontal. So they put some horizontal velocity into the rocket. They push the rocket, you know, at the time, the nose is, at the time of lighting those engines, the nose is facing the horizon and the engines are facing the opposite horizon. So you now shot it a decent amount in an off, you know, the direction that you're not falling, you know. So you have to factor that in. To where you're landing because you're going to land on this precise, in this case, you're going to land on the inside the arm, the loving arms of the chopsticks, you know, the Creed arms wide open and try to land inside this.

• 2:16:57Lex Fridman?

  Exactly, the song that you're playing through my head as I watch this now. Thank you. Thank you for forever joining those two. I appreciate this.

• 2:17:06Speaker 01

  And you have to very precisely control. So what you have to do is now that it's done that kick, you also have to cancel out that horizontal velocity. So it's actually going to rotate beyond 90 degrees to cancel out that horizontal velocity. And then modulate the engines to make it so the thrust, you know, is, is perfect so that it can control itself into a controlled landing. And all this is done in like 500 meters, like 1500 feet. You know, you're doing all of those things stupidly close to the ground. It looks absurd. So far they've done five of these tests. All, the first four all blew up, you know, they're all coming in from about 10 kilometers or 33,000 feet. Falling, flipping, you know, again, this thing is huge that just the booster or just

• 2:17:51Speaker 01

  the upper stage of this is, is like 50 meters tall, you know, so it's 150, it's like 45 meter, about 50 meters tall, about 165 feet tall, nine meters wide, so 30 feet wide. It weighs, you know, something like, God, I don't remember if it's something like 120 metric tons, 120,000 kilograms, you know, two quarter of a million pounds empty. And it's doing this flip maneuver. It has to do all this perfectly. So the first four, four attempts of this were pretty spectacular failures.

• 2:18:19Lex Fridman?

  So just to clarify, which stage is doing this maneuver?

• 2:18:22Speaker 01

  It's the upper stage is doing this belly flop maneuver. Yep.

• 2:18:25Lex Fridman?

  So this is the, the stage that would presumably have humans on board if we were to use.

• 2:18:33Speaker 01

  And if things continue to play. Now here's, here's something I would love to see.

• 2:18:38Lex Fridman?

  Yeah.

• 2:18:38Speaker 01

  Just saying this.

• 2:18:39Lex Fridman?

  Yeah.

• 2:18:40Speaker 01

  If you already have these big aero surfaces, the flaps, they also have to move. They're on heavy motors and hinges and flaps and all that stuff. I'm actually surprised that for Earth, they aren't just looking at landing it horizontally on a runway like space shuttle.

• 2:18:55Lex Fridman?

  Oh.

• 2:18:56Speaker 01

  I mean, that worked. The Brond did it. You know, the Soviet Union's Brond. I rolled my art real hard there, so.

• 2:19:03Lex Fridman?

  Wow.

• 2:19:03Speaker 01

  Wow. Really good.

• 2:19:05Lex Fridman?

  I'm very impressed. I'm very impressed.

• 2:19:07Speaker 01

  Oh, and you know, the Brond did it. We have other space planes like the X thirty seven B. We have the upcoming Sierra Nevada's Dream Chaser. It's, yeah, you have some extra mass in the wings, but so does Starship. Starship has the extra mass of those flaps and you know, the motors and the hinges and all that stuff. I would like to see the trade on like, is it actually lighter weight to do that versus doing what SpaceX is doing? So, yeah, I mean, that's the, that's the funny thing. I think realistically, if Elon walks in the door tomorrow and says, guys, we did some simulations and actually it's like, we can get another 5,000 kilograms into space if we just land it horizontal. If we kind of give up on our ego and land horizontally, at least on Earth, then you know, I think they could be doing that pretty quickly. Cause

• 2:19:52Speaker 01

  that's the thing is, this ultimate thing has been to land on Mars and you know, other planets. And Mars doesn't have a runway, doesn't have a, you know, thick enough atmosphere to utilize aerodynamic flight like that. So you have to do propulsive landing for Mars. You're going to land on a unprepared surface, you know, so it has to be able to do this at some point. The ultimate, it sounds ridiculous and it is, but the ultimate goal of it is to land on Mars.

• 2:20:17Lex Fridman?

  There's not much of an atmosphere to like, to help you with the, for the belly flop to be useful.

• 2:20:23Speaker 01

  There's only 1% the atmosphere on Mars as there is on Earth, but you still want to utilize as much of that atmosphere as possible. So in the upper atmosphere, it's still going to be coming in more or less, kind of perpendicular to the airstream. I guess it's probably more like, you know, 60 degrees, 70 degrees to the airstream, like where it's belly flopping. And it's going to especially do that on Mars. It's going to need to, you know, use up as, let the little bit of atmosphere there is, you know, you're coming in at insane velocities. And so even that 1% thin atmosphere is still going to do a lot of work. Now, on Mars, there's only 38% of Earth's gravity on Mars. So the belly flop maneuver is a lot, it could be a lot more conservative. You could

• 2:21:04Speaker 01

  Do that at like 5,000 feet up and it just wouldn't matter as much because there's not as much gravity loss or gravity drag. So you can kind of just more slowly, gently, you know, you don't have to do this crazy extravagant like belly flop, you know, flip maneuver. But it would still something at some point you would transition from more or less perpendicular to the airstream to, you know, and horizontal to landing vertically.

• 2:21:28Lex Fridman?

  I like how we're having this old boring conversation about the differences of landing on Earth versus on Mars. This is surreal that this is actually a real conversation, that this is something that we're discussing.

• 2:21:43Speaker 01

  Yeah.

• 2:21:44Lex Fridman?

  Because it has to do both.

• 2:21:45Speaker 01

  Yeah. But in my opinion.

• 2:21:48Lex Fridman?

  Yes.

• 2:21:48Speaker 01

  I think we'll pretty quickly see an evolution of starship that's like dedicated versions for certain tasks.

• 2:21:54Lex Fridman?

  Sure.

• 2:21:55Speaker 01

  And at the end of the day, again, if it's, if someone runs a simulation says it's actually more efficient and it's better just to land horizontally on a runway, then that's what's going to happen. You know, it, it, it doesn't matter, but they still will develop, you know, if the ultimate goal is to land on Mars, then they'll have a dedicated Mars variant, you know, which will likely look different than the Earth variant, you know, and they'll still probably be launched on the same booster. You know what I mean? So there's.

• 2:22:21Lex Fridman?

  Oh, you mean like that particular vehicle will not be returning back to Earth? It'll need to be modified because, uh, because the ultimate is to have one starship that goes to Mars, lands on Mars, then takes off of Mars, lands back on Earth and is reused again.

• 2:22:35Speaker 01

  Yeah.

• 2:22:35Lex Fridman?

  Over and over and over.

• 2:22:36Speaker 01

  And there's a chance that you, you know, you have just a, a cycler, just a, you know, if you're, if you, at the end of the day, you're just really trying to see what is most feasible, what's the most efficient. You literally have a vehicle dedicated to Mars. Mars is easy to do a single staged orbit. It's a lot lower gravity, a lot thinner atmosphere. You can easily do a single staged orbit. You get into orbit, you park to a dedicated, you know, transfer vehicle that goes between Earth and Mars. It only stays in space. You don't have heat shields. You don't have landing legs. You don't have. All these things that you need, ideally it's nuclear powered, so it's super efficient. That gets you back to Earth. Once you're at Earth, you rendezvous again with another landing starship. And that starship might be horizontal runway starship, you know, like

• 2:23:16Lex Fridman?

  Yeah.

• 2:23:17Speaker 01

  There's no, I don't see the, and I think ultimately it'll win out where we don't have a one size fits all. I think that's the, that's the flaw of the space shuttle really is that it was trying to do everything. And it ended up kind of doing nothing well, but that's, I think what SpaceX has proven. I mean SpaceX already has variants coming. There's already going to be a dedicated lunar lander for NASA for the Artemis program. There's already going to be a tanker variant. There's already going to be likely just a pure cargo version. There's likely going to be a human version. We'll likely see evolutions of this thing happen, you know, relatively quickly.

• 2:23:49Lex Fridman?

  And when, once it's all working, it's only a matter of weeks before people riding on it will be complaining about the speed of the wifi.

• 2:23:58Lex Fridman?

  That's the old like Louis C K joke with like, you're flying on a chair through the air.

• 2:24:04Speaker 01

  Yes.

• 2:24:05Lex Fridman?

  It's incredible.

• 2:24:06Speaker 01

  You didn't even know this existed and now you're complaining about it.

• 2:24:09Lex Fridman?

  Uh, that's great.

• 2:24:10Speaker 01

  Exactly.

• 2:24:11Lex Fridman?

  Uh, so you, you tweeted, fun fact about starship by doing the flip around 500 meters versus higher up like two, 2,000 meters. The difference in delta V is 500 meters per second. That's a 20 ton fuel saving, which means basically 20 tons more you can put into orbit. That's more than Falcon nine has ever launched just by flipping later. That's really interesting. So there, that, that was the decision too, to flip close to the ground.

• 2:24:41Speaker 01

  Yeah, yeah. The closer to the ground, the better, the more, again, the more the atmosphere is doing work. And, uh, you know, we get into, that video really dives into like gravity losses and gravity drag. The more time you're spent, every, every second that your rocket engine is running. Earth is stealing 9.8 meters per second of acceleration against you. There's just inherently 9.8 meters per second squared of acceleration. So every second that engine is running. The first, a big majority of your thrust is actually being just stolen by Earth's gravity well. So if you're, the longer you're fighting that, the more inefficient it is. So idea, I mean, the best thing would be you flip at, you know, 100 meters off the ground, you light all your engines to maximum thrust and you pull 50 Gs, you know, you, you land on a dime,

• 2:25:25Speaker 01

  basically. Obviously, there's no margin there. There's, you know, and there's diminishing returns on that, that gravity loss thing and in your high thrust weight ratios. So that's a pretty good compromise. Like, yes, it looks scary, but they could be a lot more aggressive with that yet and squeeze out even a little bit better performance, but there are diminishing returns. So that's kind of the, the magic number we're, we've seen so far today, but we'll likely see that, you know, be played with.

• 2:25:47Lex Fridman?

  You've attended some of these, what does it feel like to see Starship in person? First of all, when it's just sitting there stacked? And second of all, when it's doing some of these tests, some of these maneuvers?

• 2:25:59Speaker 01

  Well, first off, if you have the freedom of traveling and happen to live within a reasonable, either by plane or car, it's worth going down to South Texas. It's, so Starbase is right on the border of Mexico and the United States and very southern tip of Texas, right along the Rio Grande. And it's, it's insane because it's right along a public highway. You can literally, anyone can drive down this, assuming it's not closed for testing, because they do close the highways during the week a decent amount while they're doing tests. But sans any of those days, anyone can just drive down and see these things up close and personal with their own eyes. Like, we're talking, you know, from 100, 200 meters away, you know, so two football fields away from the world's biggest, most powerful

• 2:26:43Speaker 01

  rocket. Imagine being able to do that during the, you know, Soviet Union and, you know, during the N1 and the Saturn V, you know, imagine just being able to drive up right next to the launch pad. There's no way, you know, and so to have this kind of access to, to this program is so incredible. The craziest thing is when you, when you're driving out on this, the, on Highway 4, it's Bumpy, it's, it's, you know, riddled with potholes now because of all the insane amount of trucks having to go out there and traffic. And you're going through this, it's just this weird, you're like, where am I? You occasionally are seeing like, you can kind of see the, I mean, you can see Mexico out your right window as you're driving down this highway. You know, you're just sitting there like, where am I? And then all of a sudden you kind of turn this corner and the trees and the brush kind of clear out.

• 2:27:27Speaker 01

  And all of a sudden you get a sense of everything on the horizon. And at that point, you're pretty much five miles on the nose or eight kilometers away. And from there you can just see through the, the heat haze, through the, you know, the atmospheric distortion. And you just see this weird, like, it looks like a city almost on the horizon, you know? There's tons of these tall buildings. There's a weird ominous launch tower thing with arms wide open and sometimes add, you know, a giant metal rocket. And it just looks so, so weird. I mean, it's, the word surreal, I think by definition, I think if you are expecting it, it's not surreal. I think surreal kind of means like unexpected surprise or whatever, you know?

• 2:28:11Speaker 01

  Even if you're expecting it, even if you've seen pictures, even if everything, it is surreal.

• 2:28:16Lex Fridman?

  Yeah.

• 2:28:17Speaker 01

  You stand there and you just go, what is this?

• 2:28:21Lex Fridman?

  And, and also, I mean, there is a, there's a kind of magical aspect to the, the, this is the place where over the next few years, we'll start as a human species reaching out there, traveling out there.

• 2:28:36Speaker 01

  Well, for sure, see the development of the rockets that I think will take us further than ever before. Be born right there.

• 2:28:43Lex Fridman?

  What's it like to witness the actual testing of, of Starship?

• 2:28:49Speaker 01

  So far, it's been high stakes. Like it's, it's been insane because those, the, the first I kind of mentioned earlier, there's been S and eight, nine, 10, 11 and 15 that have all done these suborbital hops. The highest one went 12.5 kilometers and the, the rest of the four went 10 kilometers in altitude. And then turned off the engines and just fell. Now, the cool thing about that is the general public could be about five, five miles away. So again, like eight kilometers away. And the weird thing is this rocket's slowly accelerating. They didn't want to exceed a certain speed, so they didn't have to worry about the aerodynamics of it. They just slowly climbed and it probably also to appease the FAA. They're like, here, we'll just limit the thrust to weight ratio and just, you know, make, make it so it's slow and controlled, no big deal.

• 2:29:34Speaker 01

  So it's basically more or less like slightly above a hover, just climbing for ever for minutes, for like four or five minutes, you just hear and feel the roar of this thing. Normal rockets, like after the first 30 seconds or minute, you know, they're so far away that you're just diminishing, you know, it's just, it's just fading, fading, fading, fading. You still get that rumble, that, that sense, but, but those first five flights, the suborbital hops were just, I'll cherish them forever because you just, you're watching this thing that you've driven up next to, you've seen it with your own eyes, that's bigger than most buildings in a, you know, fairly dense urban area, you know, it's this massive thing. You've stayed in there, you stood there, you look at it, you're like, wow, that's crazy. You've seen people working on it, their little ants compared to it.

• 2:30:18Speaker 01

  Then you drive away and you see it on the horizon and all of a sudden that thing leaves. It starts moving. Hovering. Hovering. Essentially. And the first time, I mean, you know, you put, for me at least, I put my hands on my head when I, I just, I can't help it. I'm not, it's not, I don't know. It's surreal, like you said. I don't know what in human nature decides this is what to do when you can't believe something, but that's what happens. And when that thing first took off, it was just like, my brain couldn't process seeing, you know, because I had spent so much time driving around and seeing it and all of a sudden you're watching it just take off and you're like, it's moving and all these, you know, the most complicated rocket engines ever made are all firing simultaneously and it didn't blow up on the launch pad and slowly increasing.

• 2:31:03Speaker 01

  And it's just crazy and the sound, the everything about it. And so by the time, the first one is specifically is, is December 2020 was the first SN8. It went up and I actually, we all lost it in the sky. We couldn't quite see it, but our, we had telescopes and, and, you know, high telephoto lenses tracking it. And what's funny is there is a pretty strong wind up there at altitude. And it was moving, there's a lot of gaseous oxygen being vented out of the rocket. And it's, you know, being blown by this air. So it looks like it's moving actually quite quickly, like away from us, like it was strafing to one side.

• 2:31:45Speaker 01

  So I'm watching the monitor, I'm going, oh my God, they're moving it like over Brownsville. And we're all, all of us, everyone on this, this hotel balcony is looking out down like way out over, you know? And we can't find it. And we're like, where do they lose it? Like we're thinking like, oh my God, this is going to crash down in Brownsville. And, and finally they shut the engines off and we're watching it fall. And again, we're tracking it. We know it's falling and it's falling, falling, falling, it's falling super controlled. And we're like, oh my God, this is perfect. And all of a sudden it clicked and I see it with my, you know, my eyes, I finally like tracking it. It's, it's straight out, like straight in front of us. And it looks like, it looks like it was a blimp, just barely moving. Now, cause it is falling slowly, thanks to all of its drag.

• 2:32:30Speaker 01

  And again, that's one of those moments, I'm like, it's falling so slow, you know? Cause it's so big, it's so massive, it's falling sideways. You know, I've seen Falcon nine boosters and Falcon heavy boosters and they scream, they come in so fast. And you can barely even see, we can just barely track them. All of a sudden they light their engines and they decelerate so quickly. This was like the opposite. It was like, is that thing ever coming down? It was just falling so slowly and so right there, it just felt like it was so close. And so when it finally lit its engine and it flipped, I was losing my mind. Cause I'm like, it's working, you know, this crazy plan, this huge massive thing is doing this absurd feat. And the first one, well, the first four again, didn't work out as planned, but getting to that point already, getting to that flip maneuver was a huge milestone.

• 2:33:15Speaker 01

  And it was so exciting just going through those, those firsts were amazing. And I think, you know, we're coming up now on them doing the full stacks of the booster and the upper stage. I think when we see that fly, when that leaves Earth for the first time, it'll be, like I said, almost twice the amount of thrust as anything else. It'll be the biggest, heaviest, largest thing to ever fly. It's going to shake everything. I can't wait.

• 2:33:41Lex Fridman?

  Have all 33 Raptor engines been active at once? Have they tested that?

• 2:33:46Speaker 01

  No, that's coming up. That's kind of the next milestone. I don't know, you know, when this will come out, but we're, that's like the next.

• 2:33:53Lex Fridman?

  Just a few days, very quickly here.

• 2:33:54Speaker 01

  It then, but if people listening to this, if they're listening to it early on, they'll likely be able to catch, you know, I think at this point, it seems like next week.

• 2:34:01Lex Fridman?

  So step one would be static fire?

• 2:34:03Speaker 01

  Yep. Holding on to the rocket and lighting up the engines. And so so far they've lit at most, they kind of, they went for like a more than 14 engine static fired. I don't recall if it was like, you know, 16 or something engines lit at once and they ended up going down to 14 engines. That's the most engines they've ever lit. So the next step and the final kind of step before they fly this thing is they're actually going to light all 33 engines simultaneously. And although that sounds scary, let's not forget the Falcon Heavy that's now flown five times completely flawlessly has, has 27 engines running simultaneously. So they definitely have, you know, SpaceX has experience with high number of engines

• 2:34:44Speaker 01

  running at the same time, but it is still like, this is going to be a lot of moving parts and a lot of potential and a lot, just a lot of everything.

• 2:34:54Lex Fridman?

  What are the upcoming milestones, expected milestones? And I think there's one in particular I'd like to talk to you more about, but leading up to that, of course, is like, what are some of the tests here on the way? So is the static fire, the fully stacked with the two stages? Will there be, and then all that leading to an orbital? Launch, test, what, so what are the things we should know about? And what do you think, like, what do you think the timeline will be with like the orbital test?

• 2:35:30Speaker 01

  Timeline, the reason that we have this website, the expected milestones, is because I always tell people to ignore any time you ever hear for any of this stuff.

• 2:35:37Lex Fridman?

  Yeah.

• 2:35:38Speaker 01

  Just pay attention to milestones because when you're doing stuff for the first time, you know, you just have no idea.

• 2:35:43Lex Fridman?

  So just to understand the expected milestones here, the first column is the event, the, the second column is the date and status TBD, complete, green means what?

• 2:35:54Speaker 01

  Green means it's been completed and it shows the completion date there.

• 2:35:57Lex Fridman?

  And the completion date?

• 2:35:58Speaker 01

  Yeah.

• 2:35:58Lex Fridman?

  And then the others, may, maybe more, maybe not for the full, full stack testing, the de-stack and the, there's a 33 engine.

• 2:36:07Speaker 01

  So, so realistically, we're expecting them to de-stack and SpaceX, I think, just tweeted that actually, that they're going to be de-stacking the second stage from the first stage, kind of get the ship safe while they test. Because they don't want to, you know, 33 engines is pretty high risk if they do blow up the rocket. When they test it for the first time, it's not going to be fully fueled, I don't think at least. But there is a limit to how, they do have to have it weighed down enough that the launch clamps can hold on to it. Because if you think about it, like, normally the launch clamps are holding on to an entire rocket weighing 5 million kilograms, 5 million, you know, it's weighing an insane amount. So those clamps don't actually have to hold 75 mega newtons of thrust. They really only have to have to hold down 25 mega newtons of thrust. You know what I mean?

• 2:36:52Speaker 01

  They're not designed to hold down all 75. They do have to have enough weight on the rocket so that, so even when they do these, the testing of the 33 engines, it'll have to have enough propellant in there that they don't exceed the clamping and the holding force of the stand. Otherwise, it'll break free from the launch stand and that booster will go flying off uncontrolled.

• 2:37:09Lex Fridman?

  So it's a difficult thing to figure out in the test, how many simultaneous things you test, right?

• 2:37:15Speaker 01

  So they're kind of mitigating risks, which is why like their de-stack, you know, they don't want to have, although the ship could be on top of it to help weigh it down and simulate the, you know, the launch environment better, at some point, that's a risk they're just going to take when they go for launch. And so for now, they're taking the ship off in case something goes wrong during the 33 engine test. And then, once we see if the 33 engine test goes well, hopefully, we see the the second stage get stacked back on it. We'll see him get closer, like, closing out all the items and hope. The big one, too, is the FAA launch license. There, that's a, that'll be publicly filed. We'll see that, you know, in the system, having a launch license. And I, I have no sense of that type of thing. You know, that's outside of, but that's, but that is a big milestone. And it might be something that could potentially hinder, you know, hold

• 2:37:59Speaker 01

  up the launch date, would just be waiting for a launch license.

• 2:38:02Lex Fridman?

  Yeah, I'm sure there's a lot of fascinating bureaucracy and politics and legal stuff and all that kind of beautiful, magical thing when you live in reality. Because it is, I mean, it is a big rocket.

• 2:38:17Speaker 01

  Yeah. Well, and the biggest thing, it's not so much, the FAA doesn't necessarily care about the success of the rocket. They did really just care about the safety of public and public property, you know. So it's, it's, it's a matter of being convinced and having the, the data to prove, okay, if this thing blows up, we have a control of how and when it blows up. We have control of, you know, X, Y, and Z. Here's the potential damage. Here's the blast radius. You know, this, again, is over twice as powerful and twice as much potential. Actually, it's, it's a lot more potential for an explosive energy. If it, you know, where it happened to, well, the, let me walk back a little bit, because in order to have a real detonation, you have to have a perfect mixture ratio

• 2:38:59Speaker 01

  of, of your fuel and oxidizer. If, when a rocket blows up, typically, you know, it kind of unzips, and some of the fuel will mix into some of the oxidizer, and you could have some explosive energy. But a lot of it's actually just a deflagration. It's just, you know, flames. And, and there will, there would be explosive energy, but it's not like you're lighting all of it simultaneously. It's this giant bomb. It's just really not. So that's good. But at the same time, even in those circumstances, the amount of energy is still absurd enough to likely blow out windows, you know, for miles and miles and miles, including my studio space.

• 2:39:35Lex Fridman?

  Well, if the cameras hold up, it will be one heck of a show. Hopefully, of course, would not would not happen. So how does that take us to an orbital launch? When do you think that would happen?

• 2:39:47Speaker 01

  In my opinion, this is a very fluid, and this will change literally by the hour.

• 2:39:52Lex Fridman?

  So you really think that it's very difficult to really say like, even even for something that could very well happen this year, even just a few months away, you're making a prediction. By the way, are you like, superstitious on this kind of stuff a little bit? Like, you don't you're worried about jinxing it and that kind of stuff?

• 2:40:09Speaker 01

  No, not at all. No.

• 2:40:10Lex Fridman?

  Because I would imagine you would be like, waiting for all of these launches that keep getting delayed, where you start thinking that there's certain things you do will control the weather.

• 2:40:19Speaker 01

  My socks. Why am I wearing these socks that just scrubbed again? You know, like, yeah.

• 2:40:23Lex Fridman?

  You're lucky. You have to wear the same lucky socks. Otherwise, it's going to there's going to be bad weather.

• 2:40:29Speaker 01

  So the reason that I say this and why it's so difficult is they did a first full stack test in July of 2021, and the expectation was we're a month or two away from a launch.

• 2:40:39Lex Fridman?

  Yeah.

• 2:40:39Speaker 01

  So like, realistically, for 18 months, I've been in a purgatory, thinking that we're a month or two away of an orbital launch. Now, I did say, for the record, when that thing stacked and when a lot of speculation was saying, you know, a month or two, I was saying, I don't expect it to fly in 2021. You know, and I've been just saying, I just saw the amount of work that still needed to be done, like on the ground systems, the tanks, the the launch mount, all the stuff. I'm sitting there like, there's still a lot of stuff. They're going to have to validate it. They're going to have to test everything, every component. And, you know, people were like, how dare you say that even Gwen Shotwell, the president of SpaceX is saying Q3 of 2020? I'm like, OK, but like, I'm just, I'm not going to be surprised if it slips into 2022. And here we are, the beginning of 2023, and I, I think we're finally within like, two months.

• 2:41:25Speaker 01

  I I'm expecting, like, I'm trying to keep my March and April as free as I can. We'll put it that way.

• 2:41:32Lex Fridman?

  I love it. Actually, just a small tangent on Gwen Shotwell, like, what do you, from everything I know, she's an instrumental, a really crucial person to the success of SpaceX in running the show. She's the president, the COO. What do you know about her that sort of the genius of Gwen Shotwell?

• 2:41:56Speaker 01

  Man, my understanding is she's really the glue. You know, she's the glue to the tornado.

• 2:42:02Speaker 01

  Tornado comes in and then she comes around and just really executes on, on and, and helps. You know, a, a famous story is that at some point Elon walked in or she sprinted into a meeting because Elon was actively trying to cancel Falcon Heavy, saying it's too far, like it's too much development, it's still too far away. And this is like, you know, this might've been like end of 2017 or something and it flew for the first time in 2018. So we're, we're talking like it's close to the end of development. You know, there's hardware being built, all this stuff. And Elon's literally in a meeting telling people they're going to cancel it. We're going to move on to BFR or now Starship and just go full steam ahead on that. And she runs into the meeting and reminds Elon, we have X amount of customers

• 2:42:45Speaker 01

  have already purchased a ride on Falcon Heavy. We can't delay that. You know, so it's, it's that business sense of like we, yes, it's great to innovate, but we also have to pay our dues and, and, and make the money to continue our operations. And I think she's just a lot better at, she has, I think she has such a great perspective on everything. It really seems like everything, she, she doesn't, I wish she did more interviews because I would love to hear more from her. But man, like it just seems

• 2:43:11Lex Fridman?

  Hear that Gwen?

• 2:43:13Speaker 01

  For both of us.

• 2:43:14Lex Fridman?

  Yeah. She hasn't actually done that many interviews, right?

• 2:43:17Speaker 01

  Not really. No. She's done like a TED Talk, a couple of little things here and there, but not really many interviews. And, and I would just love to hear like what, you know, what on a daily basis, like what is she doing to keep her head on and, and keep everything so organized? You know, it's, you know, my, yeah, I, my understanding is that she, she is absolutely integral and, and does just a insane amount of work at SpaceX.

• 2:43:42Lex Fridman?

  Yeah. I mean, the, so it's the, the project planning, but also the, how the teams integrate together and the, and the hiring and this is the management.

• 2:43:50Speaker 01

  I think it's a lot of it. Honestly, even just the business, making sure the money's flowing in a positive trend, more or less, you know, that yes, Elon's obviously a money guy, but he thinks he's so, I think Elon is so risky, you know, he just loves to throw it all in that he leaves little margin for error. You know, he's, he's been really lucky with rolling his dice, you know, especially like when he started SpaceX and Tesla, that was the ultimate roll of the dice. But I think she's a healthy balance to be like, well, here's our, you know, operations and how we can continue to do this without risking everything, you know? And Starship's close. Let me be clear. Starship is close to risking everything already. It's just such a big, fast-moving, high-risk developmental program that like,

• 2:44:35Speaker 01

  I personally think SpaceX would probably be fine if they shut the doors on Starship and just flew Falcon 9 and Falcon Heavy for the next 10 years. They would still be commercially valid. They could not spend another dollar on research and development. They could fire, I don't want them to, fire everyone involved in anything research and development and just ran operations on Falcon 9 and Falcon Heavy. And they would still be dominant for 10 years and they would still have a business case and they'd still be fine. But they're all in, like all chips are pretty much, as many chips as possible are in.

• 2:45:05Lex Fridman?

  I don't know what else I could say is there's not, I've talked to a lot of great leaders. There's just not many people like Elon that would push for Starship.

• 2:45:19Speaker 01

  When they're already as far ahead.

• 2:45:21Lex Fridman?

  Very successful company.

• 2:45:23Speaker 01

  Yeah.

• 2:45:24Lex Fridman?

  Sort of everyone doubted that it could be a successful company. It was so close to bankruptcy and failing. And then to take it into a financially viable, successful company. And just when you do, you take on a project that again risks everything.

• 2:45:41Speaker 01

  Well, he already did this with Falcon 1 to Falcon 9. Like literally people were like, what are you doing? They basically signed over and were fully ramping up Falcon 9. By the time they finally had their first Falcon 1 success, they had one more flight. They only flew Falcon 1 successfully twice. They flew five times altogether. The fourth one was successful and they flew one more time. And anyone else out there would have been like, let's keep flying the Falcon 1. We have a working rocket. We can start making money and profiting. And already he was risking it all and saying, nope, we're going from Falcon 1 to Falcon 9. It was a huge, huge leap. You know, I think it's at least as big as a leap from Falcon 1 to 9 as it is from Falcon 9 to Starship or around relatively a similar leap.

• 2:46:25Speaker 01

  So it's just that same thing again. People are going, why are you leaping into this insane program and system and risk? When you have such, you know, you finally have this workhorse of a rocket that's so dominant in the industry, yet they're going.

• 2:46:41Speaker 01

  10x, you know?

• 2:46:43Lex Fridman?

  It so happens that you've been selected for the Dear Moon mission that will fly Starship once around the moon with nine people on board. You are one of those people, so just pause to take that in. Everything that we've been talking about, you will not just be reporting on, you will be a part of it. So tell me about the objective of this mission and how does it feel to be a part of it?

• 2:47:15Speaker 01

  Well.

• 2:47:20Lex Fridman?

  Man.

• 2:47:22Speaker 01

  Yeah, it's basically it's the Willy Wonka of space. Like generous, a generous individual purchased a ride from SpaceX as early, at least as far as I know, the earliest I knew about it was February 27th, 2017.

• 2:47:41Lex Fridman?

  Who's the individual?

• 2:47:42Speaker 01

  Yusaku Miyazawa, but at the time, I'm telling you a story. At the time, we didn't know.

• 2:47:46Lex Fridman?

  Okay, great.

• 2:47:48Speaker 01

  So February 27th, 2017, a press release comes out from SpaceX saying, someone purchased a ride through us around the moon. We're gonna fly someone around the moon. And at the time, it was on a Crew Dragon capsule and a Falcon Heavy. It's like, wow. And that was enough, that little moment right there, that press release. So first time, I'm like, I'm gonna make a YouTube video about this. I stood up, turned on my camera, put on my, at the time, space suit. And I basically yelled at the camera for three minutes about, someone's going around the moon, you know? Fast forward to 2018, end of 2018 and near the end, they introduced, there's a SpaceX press conference. I'm, I'm there as a member of the press. I'm reporting on, we're going to meet this person that's going around the moon and come

• 2:48:32Speaker 01

  to find out, boom, they're going to be riding on Starship now. They changed from Falcon Heavy and Dragon. SpaceX is no longer going to do that. They're going to upgrade them basically to Starship. So instead of being in like a small tin can, they're in this giant luxurious, you know, mega rocket around the moon. And it comes out that this individual named Yusaku Miyazawa, who is a Japanese billionaire, purchased this ride. And instead of inviting, you know, his friends and, you know, colleagues and whatever, whoever's family members or whatever, he decided that the most impactful thing he could do with this opportunity is invite more or less artists. And the original thing was like artists, you know, journalists, a painter, an athlete,

• 2:49:13Speaker 01

  a, you know, a all, you know, photographer, videographer, you know, all walks of life.

• 2:49:18Lex Fridman?

  When they said athlete, they thought of you.

• 2:49:21Speaker 01

  Like, I know a guy. This guy rode Ragby once.

• 2:49:27Speaker 01

  But, uh, so, and at the time, you know, I was like, this is crazy. I can't believe this is gonna happen. And, you know, he had this, this vision of we're gonna find people from all around the world. I'm going to invite people from all around the world, um, from different walks of life, different, different, you know, trades. And I'm going to share this experience so that they can share it with the world and really have an impact much greater than, you know, any one country or any one individual or any, you know, set of military trained, you know, astronauts could, could do, offer up a new perspective. Beautiful. I literally, I mean, at the press conference, I, I cried, like, I had a couple tears in my eyes. I was like, this is so cool.

• 2:50:03Lex Fridman?

  Could you just pause on that? So he goes by M Z?

• 2:50:05Speaker 01

  M Z, yep.

• 2:50:08Lex Fridman?

  How incredible is that?

• 2:50:09Speaker 01

  It's, I'd like, uh, I, I, I think it's, you often don't realize the importance of

• 2:50:16Lex Fridman?

  individuals in human history, like they, they, they define, because this, this could be, we talked about the importance of Elon in particular, you know, most of the work is done by large groups of people that are collective intelligence that we band together. But like, these individuals can be the spark of the catalyst of that progress. And I mean, just this idea of getting. Not just civilians, which is already incredible, but civilians with a sort of an artistic flame that burns inside them, they're able to communicate, whatever they do, are able to communicate something about that experience. It's just a genius idea to spend quite probably a very

• 2:50:57Lex Fridman?

  large amount of money for that. I mean, it's, and that will be part of history.

• 2:51:05Speaker 01

  Yeah. And it's easy these days for people to be cynical, you know, especially about like spaceflight and wealthy individuals. But really, in my opinion, and maybe, you know, just the time I was just so couldn't believe this, this idea. You know, I'm someone that has studied a lot about, you know, the Apollo program, the people that have been to the moon and they're incredible individuals, incredible individuals, but they're so saturated with tasks, you know, and they're military trained and often that they didn't really have the luxury of just being able to soak in the experience of going around or to the moon and seeing the moon up close with

• 2:51:44Speaker 01

  your own eyes. Like, that just psychologically has to be insane. And so to have this opportunity to be able to observe our closest celestial neighbor with your own eyes and your sole purpose is to soak it in and share it and communicate and create with the rest of our planet, like that to me is just beautiful.

• 2:52:07Lex Fridman?

  So that is the objective of the mission?

• 2:52:09Speaker 01

  That right there is the objective of the mission.

• 2:52:11Lex Fridman?

  And how does it feel to be selected as one of the nine to do it?

• 2:52:18Speaker 01

  It's, it's, it's a, it's a gradient. It's slowly, it's doing a few things. Since I've known, it's become, I think the closer it gets, the more excited and the more nervous I get. You know, it's a

• 2:52:32Lex Fridman?

  And the more real it becomes?

• 2:52:33Speaker 01

  The more real it becomes. You know, the announcement was a big, it just got announced at the end of 2022 publicly. Who's involved? And so, you know, prior to that, like I had, you know, each step of the selection process, you know, there's a pretty comprehensive selection process with interviews and stuff. Each, each step I'd try not to get my hopes up. And frankly, like this, let me be clear, this was not something that like I've always wanted to do. You know, it's not like I'm out there. I didn't start doing YouTube videos because I wanted to even go to space, like none of that. I, and I've said hilariously, I've probably said dozens or hundreds of times on air, like, yeah, I don't ever want to go to space because it's not like my, it's not a driving force. It's not really a thing I even really, truly pictured or let myself fantasize about, frankly. So each step of the selection process, I didn't really let myself

• 2:53:18Speaker 01

  dream about it too much, or, you know, but it kind of, it kind of chip away like, oh my God, this is actually becoming more real. This is actually more and more of an opportunity and I get equally more nervous too. Like, you know, frankly, is it's I've, I've, you know, I've seen spaceflight stuff go wrong. I've, you know, I, I think about this stuff a lot. So like, yeah, I get more nervous, but I also get more excited about that opportunity. Like it's an opportunity that how can you pass? And it's still, I still have to actually stop, pause, think, and actually realize the reality that like, that I am going to the moon. I'm going to see the moon up close, uh, flying around the moon. I'm sorry. Some people get mad when I say going to the moon since I'm not landing on it. Um, but flying around the moon, seeing the far side of the moon with my own eyes.

• 2:54:02Speaker 01

  And seeing earth. And seeing the earth rise behind it. Yeah. It's going to, I just, I can't, I can't tell you what it's going to be like and feel like. So epic. But it's insane to me that like, we're having this conversation and that that is my, my reality, you know, like, and that someone was generous enough to consider the option of, of sharing this with, with frankly strangers. Yeah. And the, the process that they had for selecting, like how, um, how much thought and time went into the selection process is incredible. You know, they did a public call at the beginning of 2021. And so the the teams involved in in whittling it down from a million applicants. There's a million applicants that whittled it and they got it down to to eight crew members and and two backups.

• 2:54:47Lex Fridman?

  Yeah.

• 2:54:49Speaker 01

  Amazing people. I would have, you know, I don't know how they wound up where they did, but it's it's incredible. I feel very deep connection to everyone that's already involved in.

• 2:54:59Lex Fridman?

  What can you say about the crew? You've gotten the chance to meet them and talk to them and Steve Aoki is on the crew. Like, who else is there? So you are obviously the star athlete. Who else in terms of the artists that are there?

• 2:55:13Speaker 01

  So, oh, man, we might just want to pull up just so I don't totally butcher and forget anybody, but because so far I haven't actually had the chance to meet everyone in person, you know, so far a lot of this was done during the pandemic, but we've met through a couple of different things. We've had a couple of different times to get together. But so so far I have not met Steve Aoki yet or Top. We've been on calls and stuff. I also have not yet met Dev Jashi, who is an actor from India. So, yeah, we can Steve Steve Aoki, American DJ and producer and musician. Top from South Korea is also a musician and a producer.

• 2:55:49Lex Fridman?

  So this all across the world, like truly global, all different kinds of walks of life.

• 2:55:54Speaker 01

  Yes.

• 2:55:54Lex Fridman?

  All artists of different forms.

• 2:55:55Speaker 01

  And Steve is Japanese. His parents are Japanese, but he, you know, lit born and raised in the United States. Yemi is a dancer and choreographer from the Czech Republic. Rhiannon is a fine art photographer from, well, England and Ireland. I guess she lives in both and kind of a bit of a, she's all over the place. Technically, she's Irish, I guess. I, Tim Dodd, yep, that's me from the United States. Then you have Kareem, who is from England and does also is a photographer and documentarian, does a lot of work with oceanography and volcanoes. So he does really incredible work. Brendan Hall is a documentarian

• 2:56:37Speaker 01

  and filmmaker. Dev Jashi, sorry, Brendan is also from the United States. Dev Jashi is an Indian actor.

• 2:56:45Speaker 01

  I believe also, I believe he's also already been producing and things. He's very young. I think he's only like 19 or 20 and he's, I mean, he's been acting since he was like five years old or something. He's a, he's a Bollywood star, like he is a star in India, which is really cool.

• 2:56:59Lex Fridman?

  Right.

• 2:57:00Speaker 01

  Kaitlin Farrington from the United States is an Olympic gold medalist snowboarder. So she, believe it or not, is the athlete and not me. And then, and she's one of the backup crew members, as, as, as so is Miyuu from Japan, who's a dancer.

• 2:57:17Lex Fridman?

  That's amazing. It's such an interesting group. I mean, is there something else you could say about MZ? About Yasaka Miyazawa?

• 2:57:24Speaker 01

  Yasaka Miyazawa. So he, he's also a musician. So he was actually in like some kind of punk hardcore Japanese bands in the early, in the 90s and stuff and early 2000s. He started a, a record company and, and distribution and sales ended up in, in fashion and owns one of the biggest fashion companies in Japan. And has become a fine art collector and just kind of a philanthropist and.

• 2:57:49Lex Fridman?

  And he's been out to space already.

• 2:57:51Speaker 01

  He's already not only been to space, like, you know, he's been to the International Space Station. He's been on orbit and on the ISS. And so he, what's cool is like, you know, there's talks of, frankly, to be, to be honest, like we still, I still don't know all of the details about this, you know, we're not yet into training. I kind of always assumed prior that there'd be some professional astronaut, you know, when they talked about it in 2018, there's talks of we'll have a professional astronaut on board. But realistically now, like MZ is a trained astronaut, you know, he has trained a lot, like six months, you know, plus to be able to fly on Soyuz. So as far as like, it's good to know for me that I have someone on the crew that has experience with spaceflight, has trained and

• 2:58:35Speaker 01

  has some knowledge on spaceflight as well. You know, that's, that is an important aspect for sure.

• 2:58:39Lex Fridman?

  So you made an excellent video about flying in the fighter jet that I think you mentioned may be relevant to the training. Is there some high level aspects to training that you anticipate that you might be able to speak to?

• 2:58:52Speaker 01

  Yeah. So, you know, so far I think we can really lean on what has happened with the other, you know, commercial crew missions and in, in private missions like the Inspiration Four mission or Axiom, where SpaceX flew individuals. They trained for about six months, a lot of like reading manuals and learning the spacecraft.

• 2:59:11Lex Fridman?

  Are you gonna do like a Rocky IV montage or?

• 2:59:14Speaker 01

  I hope I just get shredded. I hope it's physical, a lot of physical training.

• 2:59:18Lex Fridman?

  And they're like, we didn't tell him to do it. He's just seems to want to fill himself shirtless in the snow. Doesn't make any, how is this relevant?

• 2:59:27Speaker 01

  Why is he always doing this? I can't get him to stop punching meat. Um, so yeah, hopefully, uh, realistically, I

• 2:59:35Lex Fridman?

  Lots of manual reading. I like it. But there's, there's a physical component to all of this and that's, that's really, I mean, that, that's fascinating. It's also inspiring, the sort of civilians can do this. That's, that's really interesting.

• 2:59:49Speaker 01

  Yeah. I mean, this is, and to me, this represents this and the other commercial space, you know, private spaceflight missions like this represent really a turning point, like truly an inflection. And again, it's easy for people to be cynical that, oh, you know, why are people wasting all this money doing spaceflight stuff? It's like, well, I'm sure some people were saying that same thing about, you know, airplanes and, and early aviation going like, why are we, can't believe those people are wasting the governments, you know, funding these stupid planes and stuff. How's this ever going to benefit me? And nowadays, like, imagine if all the planes just stopped working. Like, we'd freak out. It's like our economy would collapse.

• 3:00:25Lex Fridman?

  Yeah.

• 3:00:25Speaker 01

  It would suck, you know? And I, you know, it might be a long time before we get to that reality with spaceflight. Well, I, no, if, if spaceflight halted today, you know, space assets, all of our, you know, on orbit assets, our life would be crippled. And I don't think people realize that.

• 3:00:40Lex Fridman?

  Yeah.

• 3:00:41Speaker 01

  So it's already, we're already reliant on it. But now we're getting to the point where it's, we're really turning that corner where it's the average person alive today. You know, if you're born, uh, you know, now, from now on, I think there's a real decent chance that by the time you pass, there's an opportunity to have flown in space.

• 3:00:59Lex Fridman?

  Yeah. I mean, I, if I'm being honest, I still haven't lost the, the feeling of magic of flying in an airplane. I often catch myself thinking like, how is this real? How is, and like,

• 3:01:12Lex Fridman?

  The contrast of this incredible thing that's incredibly safe, flying through the air, taking off and landing, while everyone else just looks bored, watching like, I don't know, uh, some romantic comedy on their phone. With wifi.

• 3:01:31Speaker 01

  Yeah.

• 3:01:32Lex Fridman?

  So, yeah, it's just, it's like, the contrast of that is like, wow, we're, we're incredible, we're incredible as a society. And it's like, we, we develop some amazing technology that improves almost immeasurably our quality of life, and then we take it for granted, and now still reach for the next thing, the next thing. And life becomes more beautiful and complex and interesting. Yeah, it's just, the same stuff will be, uh, happening.

• 3:02:02Speaker 01

  Oh, yeah.

• 3:02:03Lex Fridman?

  With space travel.

• 3:02:04Speaker 01

  Oh, it'll become mundane and boring at some point.

• 3:02:07Lex Fridman?

  The tough thing about space travel, of course, you know, I don't even know if it's such a giant leap over airplanes, because airplanes are already incredible. But the tough thing with space travel is the destination, right? Is the, is the, is the landing on a whole other worlds, whether it's docking with, with different transport vehicles or the space station, or it's landing elsewhere. And it's, it's, it really, really is incredible. I, I think you mentioned, since there's, uh, there's artists, there's filmmakers and so on. And you're all of those, uh, on top of being a great athlete. I don't know, I'll just stop the running joke at this point. But is there, have you, uh, thought about,

• 3:02:51Lex Fridman?

  um, just, just in general, like, we've offline talked about microphones and like, the, all the different ways to film space launch, uh, for, yeah, rocket launches. Have you thought about the different options of like, how to capture? How to capture this? Have you, have the team have been like brainstorming and thinking about this? Do you anticipate it being super challenging? Cause there's so many opportunities to sort of think of how to do this.

• 3:03:17Speaker 01

  So one of the fun things to remember is that Starship is huge. Like its internal volume is, the pressurized volume on Starship is bigger than a 747's pressurized volume. And it can take 100 metric tons to anywhere with enough refueling. 100, so we have in theory, very little mass and volume constraints. Unlike prior, all other spaceflight missions ever, you, you're counting, you know, grams down to, you know, and just really can't risk, you know, you have very defined parameters on what you cannot do. We're going to likely have the luxury of being able to film and capture this in a way that's just never been done before.

• 3:03:58Speaker 01

  You know, we won't be inhibited by mass and volume constraints like prior.

• 3:04:04Lex Fridman?

  Yeah.

• 3:04:05Speaker 01

  So all that said and done, I'm hoping that we'll be able to just arm ourselves to the teeth with the absolute best cameras and equipment possible, backups on backups. And, you know, and pre-wire, you know, like pre-rig things. Starship is going to be a transportation system and it has, you know, it's being built from the ground up. There's no reason why they can't put infrastructure in for cameras that are just housed in the vehicle, you know? These are talks that I'm excited to have, because I really, ideally, one of the things I'd love to do. I'm going to be pushing really hard to actually try live streaming from inside during the launch.

• 3:04:45Lex Fridman?

  During the launch, live stream from the inside, that would be incredible.

• 3:04:49Speaker 01

  Wouldn't that be?

• 3:04:51Lex Fridman?

  That's possible to pull off. That's really, really incredible. There is the magic to the live stream because like that's real, that's right there. That would, the world would tune in. That would be truly inspiring. Yes.

• 3:05:02Speaker 01

  To me, that's one of those things, a lot of people ask why they aren't doing it. Of course NASA and other individuals have their reasons of why not. You know, there's obviously some technical hurdles, but now with Starlink and other capabilities, there's. Less hurdles. There's obviously some transparency reasons why, you know, and safety reasons why it might not be a great idea to livestream a risky rocket launch. You know, the Challenger, I think, put a pretty bad taste in our mouth as far as publicizing an event and having every student in the United States tune in to, you know, a tragedy. But that's something I'm pushing for really hard, just because I think it could be magical. I think it could really connect with people in a way that hasn't been done before.

• 3:05:45Lex Fridman?

  Speaking of Challenger, have you thought about the fact that you're riding a thing, as we've been talking about, that's a giant explosive powerful rocket? Have you thought about the risk of that, the danger of that? Have you contemplated your own mortality?

• 3:06:11Speaker 01

  How could I not? You know, I've seen with my, I've seen and felt four of these prototype vehicles blow up, you know, with my own eyes. I don't know if there's anyone else. You know, early days, some of the, you know, Mercury and Gemini astronauts watched failures of rockets and then got on them. I don't know of too many people that are dumb enough to do that, though, these day, this day and age. It's, it's obviously, I will have to see a lot of successful launches and have to have a lot of confidence in the engineering, the data, that they've developed a safe system. Because currently, the current

• 3:06:52Speaker 01

  iteration of Starship has no abort system, has no escape tower. So, you know, Dragon capsule, which is currently flying people, has a launch abort system. It has Super Draco engines that, either by the push of a button or by the automatic triggering of the flight computer, can shoot the capsule off of the rocket in milliseconds and pull it safely away, get it far enough away that it can pull the parachutes and safely splash down. Starship, by all iterations I've ever seen, does not have that. The Space Shuttle also did not have that. So it's not absurd to not have an abort system. Like, it is, there is, you know, Certain engineering principles that that prove that that could be a completely valid

• 3:07:34Speaker 01

  thing. The spaceship flew 133 times fully successfully. It did have two failures resulting in the loss of 14 lives. Eighty-five, or sorry, 98.5% success rate. Pretty, I mean, yeah, there's other, I've probably done things that are a lot riskier. I have race motorcycles, drag race motorcycles, and ridden like an absolute jerk on the streets on a motorcycle. I'm sure I've had a higher than a 98.5% survival rate, or lower than that, I mean, at some point. So it's, you know, yes, it's risky, it's scary. And I think about it a lot, a lot. It definitely is one of those things that I, you know, I will have to see,

• 3:08:18Speaker 01

  and I'm in no hurry for this to happen either. You know, personally, I'm in no hurry because it's like, I would rather see this thing be developed and integrated and see 10, you know, or I was gonna say 10 dozen, but I'd be happy with a dozen fully successful, like, oh, we've got this thing totally nailed down, you know, before I get on it. But, and that likely is the reality. There will likely be a dozen or two or three launches, because just even to get to the moon on Starship, they have to refuel it in orbit. So it will arrive, get to Earth orbit, basically empty and out of fuel. So I'll have to dock with a fuel depot, fill up, and then go to the moon. So just to even get that full, you know, we're already talking about, you know, a handful of launches. So there will be a

• 3:09:02Speaker 01

  lot of launches before we fly.

• 3:09:05Lex Fridman?

  Would they do a test flight without humans on board that goes to the moon, or no?

• 3:09:11Speaker 01

  I'm not sure. I'm not sure if they'll do that exact flight profile, but by then they will have already flown, most likely the Artemis III program will have flown a Starship variant to the moon that lands on the moon.

• 3:09:25Speaker 01

  So doing at that point, you're pretty much, I would like them to test the heat shield at that entry velocity though, because it is, you know, it takes another, it's about 30% faster to get, like to go 30% faster than lower orbit to get out to a translunar injection. And although that only sounds like, oh, it's 30% faster, it's, you know, the, the reentry heating experienced by a vehicle goes up by velocity cubed, not squared. So, and not even, not linear. So it's not like if you go twice as fast, you get, you see twice as much, you know, 30% faster, 30% more heat. It's, and it's not squared. It's not go twice as fast, get four times as much heat. It's go twice as fast, get eight times as much heat on reentry. So 30% faster on reentry is actually a really, really big deal.

• 3:10:10Speaker 01

  So I would love to see that because, you know, there's certain things that I would love to see milestones that I would love to see tested out and proven before I get on board. But at the end of the day, I really do believe that just like Falcon 9 and the success of that, that they're going to push it and get all the, the kinks out well before anyone's on top of it. Nowadays Falcon 9 and Dragon is, you know, arguably the, one of the safest, most reliable and best rides you could take to, to space.

• 3:10:38Lex Fridman?

  Are you afraid of dying?

• 3:10:40Speaker 01

  Yeah, yeah.

• 3:10:41Lex Fridman?

  Is this one of the first times you get to, you're young?

• 3:10:44Speaker 01

  Yeah.

• 3:10:44Lex Fridman?

  Have you gotten the chance to think about death as one of the first times you've really contemplated it?

• 3:10:53Speaker 01

  I mean, yeah. I mean, like I said, I've had, I've had dumb moments on motorcycles where I kind of saw, you know, like I'm going to smash into this thing at 120 mile an hour and I'm.

• 3:11:04Lex Fridman?

  So you've had moments when you realized it could end just like this?

• 3:11:07Speaker 01

  Yes. Where you literally, and I, and I've, I have for most of my adult life had dreams of falling and hitting the ground and it just all, you get a ringing in your ears and it all goes black. And in my head I go, oh shit, that was it.

• 3:11:21Lex Fridman?

  Have you seen a therapist about this or?

• 3:11:24Speaker 01

  I wonder what it means. So I've, and.

• 3:11:28Lex Fridman?

  I'm sure there's a Freudian interpretation somewhere in there that I'm going to also apply to my dating life. No, the joke is, the running joke continues. Okay. So, I mean, it's, it's fascinating in general, as I hope we'll talk about in the early days of space flight, that there is, there is a.

• 3:11:48Lex Fridman?

  The task of reaching out to the stars is a fundamentally risky one. You have to take risks and of course, there's really rigorous safety precautions and so on. But it's still, it's still a risk.

• 3:11:58Speaker 01

  Well, and I think like most people that the, for me, the idea of dying isn't so much about myself. It's about those affected by it, you know, my, my loved ones, my family, you know, my girlfriend, my, my friends. You know, obviously I don't want to have this be a traumatic experience for anybody, you know? It's already going to be hard, like it's already, I know, uh, my mom gets, my, my parents and, and family and friends are very supportive. And you know, my parents are, you know, all about it, of course, but my mom is also very emotional too. So, you know, she's, so my, speaking of athletes, my brother-in-law has actually been on American Ninja Warrior, two seasons. Phenomenal athlete and even just when he competes, my mom gets so emotional, like she can't even hold it together, seeing that.

• 3:12:42Speaker 01

  So what's it going to be like when she sees her son get on top of a skyscraper and, and ascend on a column of flames into the heavens? Like that's going to be very difficult, you know?

• 3:12:54Speaker 01

  And I've, you know, I've taken them out, they've seen, they've seen Star Race and they've seen Starship. They've seen a couple of launches.

• 3:13:00Lex Fridman?

  I don't know if that's going to make him feel better.

• 3:13:03Speaker 01

  Exposure therapy, I guess.

• 3:13:04Lex Fridman?

  Exposure therapy, okay. Have you had that conversation with them about this, like before agreeing?

• 3:13:13Lex Fridman?

  To join, I mean, was, was that what the, was, or is it one of those things like?

• 3:13:21Lex Fridman?

  You, you just, you don't have that conversation. I suppose it's understood that there's a love, there's a passion here.

• 3:13:28Speaker 01

  And, and realistically, I'm not, I'm going to be convinced and statistically convinced that this is relatively safe. You know, like again, in the, in the 99s percent safe.

• 3:13:43Speaker 01

  Again, there's things that people do every day that are less safe than this, you know?

• 3:13:47Lex Fridman?

  Like you riding a motorcycle.

• 3:13:49Speaker 01

  Again, yeah, riding a motorcycle, doing wheelies at over a hundred mile an hour, not the smartest.

• 3:13:52Lex Fridman?

  Wheelies over a hun-

• 3:13:55Speaker 01

  What?

• 3:13:57Lex Fridman?

  All right.

• 3:13:58Speaker 01

  I'm not a smart guy always, okay?

• 3:14:01Lex Fridman?

  Well, you know.

• 3:14:02Speaker 01

  Formation flying in the fighter jets was likely a more dangerous thing.

• 3:14:05Lex Fridman?

  Yes.

• 3:14:06Speaker 01

  Than what I'll be doing in spaceflight.

• 3:14:12Lex Fridman?

  So as surreal as it is, we're talking about you flying around the moon. Let's rewind and talk about the origin story. What's the origin story of Everyday Astronaut?

• 3:14:27Speaker 01

  I used to be a professional photographer. So from 2008 until the end of 2016, that was my income was photography full time.

• 3:14:35Lex Fridman?

  Like you were an Instagram model and took butt pictures of yourself?

• 3:14:38Speaker 01

  Instagram fitness model.

• 3:14:40Lex Fridman?

  Fitness model, obviously.

• 3:14:42Speaker 01

  Now, I did, I did a lot of weddings. I shot 150 weddings all around the world.

• 3:14:47Lex Fridman?

  So subjects, all kinds of material, like, like, did you portrait also?

• 3:14:51Speaker 01

  A lot of portrait work and then just, you know, random like commercial things like, you know, food and beverages for businesses or like, you know, wheelchair ramp company, I shot their product, like, you know, random, whatever a professional photographer does in Cedar Falls, Iowa.

• 3:15:05Lex Fridman?

  When did you fall in love with photography with a visual medium? Do you remember?

• 3:15:09Speaker 01

  Yeah, I do actually remember I, so I drew up, I grew up drawing constantly. I, I was the weird kid that my, I would bring a sketch pad to the restaurants, like every restaurant when I was growing up until I was like 18, 19, I literally would just sit there and draw or waiting for food. And my parents like fostered that they would, you know, and I'd be the weird kid, but I'd be engaging and talking, but I'd be sitting there drawing. And I was always obsessed with realism and like recreating and, you know, visualizing things. And so when I got my hands on a camera, it was actually my dad's old Pentax that I first shot on a film camera and developing the film. I didn't personally develop, but like, you know, getting the film back, back in those days.

• 3:15:51Speaker 01

  You know, I just was like so excited about the idea that I had this visual thing that I saw with my own eyes. And now I can stop time and capture it and, and show it to other people. Just kind of like, to me, that was like the ultimate form of, of realism was like literally showing you the photons, basically that affected this film. And so I, I mean, I was, I was 19 when I got my first digital SLR, a Canon 20D and started shooting.

• 3:16:20Speaker 01

  And yeah, I just, I fell in love with it. It became like, I got a job at a camera store and, you know, basically all my extra money went into buying everything that I could at the time. And I only worked there for about exactly a year before I went into pursuing photography full time. And I basically was shooting weddings that I could travel and pay like, you know, afford to be able to do some big trips every year and develop some kind of, you know, portfolio of traveling and not necessarily like, not for, you know, I guess Instagram wasn't much of a thing at the time. It's really just, I like making big prints and having them displayed and that kind of stuff. And pretty

• 3:16:57Lex Fridman?

  Are you still a Canon guy? You still a Canon elitist?

• 3:17:00Speaker 01

  No, no, I, I moved around. I did Sony for a bit. I still kind of shoot mostly Canon glass, but adapted to either Sony, like lenses, sorry, like Canon lenses.

• 3:17:11Lex Fridman?

  Look at you. What do you think about the, these things that I'm using Sony A7 for?

• 3:17:18Speaker 01

  Great.

• 3:17:19Lex Fridman?

  It's great. See, yeah, it's a, I've, I've been, you know, I Googled around just trying to find a camera that can do video and photography pretty well. And obviously going with just like generic lens, prime, I resisted everything. My whole journey with these camera thing, I'm trying to figure stuff out. It's like, prime lenses seem so stupid. So for prime lens, it's like a fixed zoom thing. It's like, why? Cause I remember I was going to like Ukraine

• 3:17:50Lex Fridman?

  and thinking it's similar like, uh, um, yeah, very similar to space flight, but you're very constrained because you're going into an unknown environment. You go into a war zone, you go into a front, you don't know what, like, you don't know anything. And there's like a little suitcase, you have to like see, figure out like, how do you film this? What's, what's robust? What gives you like a good image versus the flexibility versus the weight? This weight is important there. You have to think about like, can you really bring like a bunch of zoom lenses and all that kind of stuff. So I had to learn really quickly, but yeah, I've, um, it's a whole journey that you've already been on, but it's, it's, it's nice to have a beginner like me, like to explore that. I think there is a

• 3:18:32Lex Fridman?

  There's a nice thing, just like, as we've been talking about with the beginner's mind, to not let equipment get in the way of like what your vision is of what a thing should look like.

• 3:18:44Speaker 01

  Yeah.

• 3:18:45Lex Fridman?

  Sometimes, like, especially if you're a professional videographer, photographer, cinematographer, whatever you call it, you can like fetishize equipment too much. You could get so much equipment. And I've interacted with it because I've been trying to learn from other people that have so much more experience than me. I think their advice is often like, very pushing a lot of equipment versus like, the final thing. Like, how do you create the art of it? Like, because to me, even photography is just like storytelling. And so, like, a lot of the discussion to me, that I enjoy, especially talking to creative people, is like, the final

• 3:19:28Lex Fridman?

  story. Like how, and I've learned, you know, like, light, light, light is a weird thing. Like, it's so interesting. It's so interesting how you can create emotion with light. Like, with a little, you can take a, like, a phone, and like, you light your face in different ways, and like, it changes the emotion.

• 3:19:49Speaker 01

  Oh, yeah.

• 3:19:50Lex Fridman?

  It's so weird. I'm like, holy shit. Because like, that's the conversation I want to have. If people give me advice how to light a scene, all that kind of stuff is great. But the reality is, that a little bit of light in a different direction, that you have to understand how that changes.

• 3:20:07Speaker 01

  The contour on your face and everything.

• 3:20:09Lex Fridman?

  And the expression that your face can, like, the, the expression that could be effectively communicated under, under different lighting conditions. And then, like, the mystery of, like, having some of your face in darkness and some not, when you can only see the eyes and not the face, when the background is visible or not. I mean, there's the, the, yeah, it's, it's all just like this interesting art form that's can be so powerful when you're telling a story.

• 3:20:39Speaker 01

  Well, and what's fun for, with me with photography and rockets, they're both like the ultimate story of compromise. Because when you start learning about photography, you learn about, you know, how the aperture affects both your exposure, but also your depth of field. Higher shutter speed affects both your exposure, your depth of field, how the, you know, a medium format camera versus a crop camera affects, you know, everything is a compromise. And price versus performance, like. There's always a compromise. You're always literally doing like a trade study of what can I afford? What's my outcome? Like blah, blah, blah, blah, blah. How fast is he out of focus or whatever? Same with rockets. Like there's a million choices and every single one of them affects every single thing. So there's always all these trades and it's so cool. You can see the same, totally different outcomes based on the same like requirements.

• 3:21:24Speaker 01

  You know, like do X, then here's how we're gonna do it. And you know, two teams of people will come up with wildly different things. When did you fall in love with rockets? So yeah, so the, the story kind of keeps going for me. So I was doing.

• 3:21:40Speaker 01

  Can't talk photography, man. We'll get, we'll go on a deep rabbit hole there. So, um, so it ended, uh, you know, I'm through all this doing a lot of weddings. I was already getting saturated and feeling like I'm not being as creative. You know, you can only shoot them so many weddings before you're like, well, now we do this pose, this pose, this pose. You know, even if like they're amazing places, like, you know, in front of a castle in Germany or something, I'm still like, well, at the end of the day, I'm, I'm not being very creative, you know? So I remember craving like some, some projects. And so I was sitting at my friend's coffee shop in my hometown in Cedar Falls, Sidecar Coffee.

• 3:22:19Speaker 01

  And I'm sitting on this red couch and I see this article from I think Gizmodo and it said, you could own the flight stick of an Apollo command module. And I knew enough to know what that meant, but that's really about the end of my space knowledge. And so I clicked on it. The clickbait got me like, I'm like, oh yeah, I'm gonna see if, you know, and see that the minimum bid was like $250,000. I'm like, okay, no, I can't own the Apollo joystick, you know? But it got me on this website called RR Auction. And so I started scrolling through that, looking for things that hadn't been bid on. And they had like, you know, at the time they're doing a huge space auction. And so I'm looking for things just out of curiosity, fun. These are cool. Like starting to really, you know, like I said, I liked space, but I wasn't like in love with it or anything.

• 3:23:00Speaker 01

  But I'm very just seeing all the stuff like it's so cool. Look at all this old history stuff. Ended up seeing a, um, there's an article for a, a VMSTK forty-four flight suit, high altitude flight suit that came from the Soviet Union and looks, you know, it's like a MiG fighter jet, fighter pilot suit, very similar to like the SR seventy-one, like kind of pumpkin suit, semi-pressure suit with a, you know, full helmet. I mean, it looks like a spacesuit, you know, for all intents and purposes, it's kind of like a spacesuit. And I just bid on it, you know, I bid like, I think three hundred and twenty-five dollars. And next thing you know, like, it arrives at my door.

• 3:23:43Lex Fridman?

  Yeah.

• 3:23:44Speaker 01

  And from that point on, like, literally, I got it out, I immediately tried to put it on, and the first thing that I do is almost die in it because I closed the helmet down on myself and locked it and didn't know how to unlock it. So I'm literally, and so as soon as I seal it up, I'm realizing I can't breathe, I'm going to run out of air. So luckily, like, there's a hose, you know, that kind of that long hose thing that normally plug into an air supply, had a little plug on the end of it, so I just unplugged it and was able to temporarily breathe through the hose until I figured out the locking mechanism. So there was my almost, that was my mortality rate thing right there. So that was probably above a ninety-eight or below a ninety-five.

• 3:24:21Lex Fridman?

  You're there panicking inside.

• 3:24:24Speaker 01

  Yeah.

• 3:24:24Lex Fridman?

  For a few seconds.

• 3:24:25Speaker 01

  Already reading like my premature obituary, like idiot dies alone in spacesuit in his living room. You know, like, just imagine.

• 3:24:32Lex Fridman?

  Yeah.

• 3:24:32Speaker 01

  That would be like Darwin Award for sure, for sure.

• 3:24:37Speaker 01

  So, um, so I get the spacesuit and it kind of.

• 3:24:41Lex Fridman?

  Literally take my breath away.

• 3:24:46Speaker 01

  You should feel bad for that one.

• 3:24:47Lex Fridman?

  You introduced Creed to me, so you should feel bad about that one. Star is wide open.

• 3:24:55Speaker 01

  Okay, so, um, so I ended up like, the spacesuit kind of like more or less haunted me because it kind of just, it sat in like my living room for a long time and I didn't know what to do with it. And I actually had a friend who is also a photographer, wanted to do like a photo, he was just kind of taking pictures randomly. He's like, hey, bring your spacesuit over, we'll do a picture. He's like, all right, you know, I walk across the street, literally lived across the street, Taylor, and I, and I put the spacesuit on, I took this funny picture and be like, this is awesome. And I got a lot of like fun out of like creating a character, you know, of everyday astronaut. Or at the time, I guess I didn't know, an astronaut. And then that kind of just continued. I was like thinking of more and more funny situations where I could have this astronaut on earth doing mundane, everyday things and came up with the name Everyday Astronaut. And originally, it was just literally a photo project, like this

• 3:25:40Speaker 01

  whole art series of an astronaut doing these things, these funny, whimsical, you know, silly, mundane things. But I was researching a lot about like, you know, I was trying to hide Easter eggs. Like, I was gonna hide in like the, you know, the echocardiogram of Alan Shepard, you know, like his first flight into space and photoshopping that into pictures and like, you know, doing all these little like facts about spaceflight, but they're just hidden little elements in these photos. And man, doing that, I just fell in love with it. I just was going over every little detail that I could learning. I was just couldn't stop learning. And I was, I was getting excited because I was like, I could be teaching people about all this exciting stuff and all the cool things people figured out, you know, 40 years ago, 50 years ago. And was trying to portray that through images on Instagram.

• 3:26:24Speaker 01

  And, you know, it, it took me a little while, but eventually I realized, you know, on Instagram, your retention rate, you're lucky if you get like, two seconds of someone looking at an image, you know, or maybe nowadays, 60 seconds of a quick little Instagram short or something. But, um, yeah.

• 3:26:40Lex Fridman?

  It doesn't give you a chance to really teach, to explore a little topic that you felt, like you felt the curiosity about the thing. There's so much to learn here. This is so beautiful.

• 3:26:49Speaker 01

  There's so many opportunities to have a light bulb go off for someone and be like, this is awesome. And so, uh, yeah, I think I started, so at the, by the end of 2016, like throughout 2016, I realized, I want to be done doing photography as a profession, and I want to pursue Everyday Astronaut. But I didn't know what it meant yet. I just knew like, I had this thing, you know, and at that time, I'd been doing it for roughly two years and had, you know, seen, I don't know, like 50,000 Instagram followers or something. I thought like, I could just be a full-time influencer now, you know, like just go around taking pictures of myself in a spacesuit and doing public appearances and write a children's book or something. I don't know. I don't know what this thing is. I'll figure it out, you know?

• 3:27:26Lex Fridman?

  Yeah.

• 3:27:27Speaker 01

  And so it basically, I gave myself like a runway of one year of 2017 of like, I'm gonna throw stuff at the wall and see what sticks. So I was doing like Twitch streams, I was playing Kerbal Space Program, which is like a video game, like a physics-based rocket building simulation game, but it's also like, it's fun and silly because you're not playing with like humans, you're playing with these little Kerbal, like little alien guys and it's fun and silly. You know, streaming that on Twitch and doing things and doing, posting some of those things onto YouTube, but finally, like I said, it actually happened to be February 27th, 2017, when SpaceX had that announcement that they're flying someone around the moon that I'm, I gotta tell people about this and stood there and made my first like produced YouTube video.

• 3:28:12Speaker 01

  And I didn't want it to be over three minutes because I was afraid that'd be way too long for YouTube. And I got it down to like, I don't know, two minutes and 40 seconds or something. And that video-

• 3:28:22Lex Fridman?

  Were you wearing the-

• 3:28:23Speaker 01

  I was wearing the spacesuit.

• 3:28:25Lex Fridman?

  The spacesuit.

• 3:28:25Speaker 01

  Yep. And very like horrible audio, it looks like it was color graded by a seven-year-old with a tan marker or something like, it just looks terrible, sounds horrible, I'm yelling, no one's happy. But, but the video, you know, did relatively well, like I had no followers on YouTube, like I had, you know, maybe 102 or something.

• 3:28:45Lex Fridman?

  Is the video still up?

• 3:28:46Speaker 01

  Yeah.

• 3:28:47Lex Fridman?

  That's great. I'll go have to watch that.

• 3:28:49Speaker 01

  It's so cringy. And as it should be, you know, your first video should be terrible. If it's not terrible, then you spent too long trying to make it.

• 3:28:56Lex Fridman?

  Yeah.

• 3:28:56Speaker 01

  So the thing that clicked for me is I had very little audience and all of a sudden that video kind of took off, you know, relatively, I think it got like 10,000 or 12,000 views. And I was like, holy crap, that's way more engagement than I'd have-

• 3:29:10Lex Fridman?

  Famous.

• 3:29:10Speaker 01

  I'm famous now. 10,000 people, that's almost my whole town.

• 3:29:15Lex Fridman?

  First of all, that is kind of crazy, like 10,000 people is crazy.

• 3:29:18Speaker 01

  Yeah.

• 3:29:18Lex Fridman?

  It's crazy, like if you, if you had 500 people attend a thing that you do, that'll be like, you're like a rock star, it's crazy.

• 3:29:27Speaker 01

  Exactly. We lose perspective, I think.

• 3:29:28Lex Fridman?

  Yeah, we really lose perspective very quickly, yes.

• 3:29:31Speaker 01

  Very quickly. So I'd made another video, this one I spent more time on and I had- Before photography, actually, I used to do like wedding videography too. So I had done my woes with videography and weddings and stuff. I hated video. Like, I thought video was the worst. Took so long to edit. You know, I love photography. It's like boom, you snap it, boom, boom, post, you're done in an hour, you know? And video is like this whole cumbersome thing. So I thought I'll never do video. And here I was making this long, what it's, the time seemed like a long, seven minute long YouTube video about how the Falcon nine lands. And again, like that one I posted and actually it did really bad and I was really upset. I'm like, I spent two weeks on this stupid video, you know, worked really hard scripting and blah, blah, blah. And then it, you know, had like a thousand views or something. It did much worse than the first video.

• 3:30:16Speaker 01

  And I was so upset and I kind of like was ready to keep throwing more spaghetti at the wall to see what's going to stick for Everyday Astronaut. And I think it was like a month or two later, I happened to like, you know, check the analytics on YouTube and all of a sudden, that video like kind of took off and it got like 40 or 50 or 60,000 views or something. I was like, no way. And it just kept, you know, that just honed it in more like, okay, YouTube will bring a bigger, like bring an audience to me as opposed to like Instagram. I had to find and, you know, try to get the audience to come to me. And this was like, they were going to do the legwork. So if I make decent videos, um, and I realized like really the, the fun thing for me was explaining a topic that was scary and intimidating and try to make it, you know, fun and engaging.

• 3:30:58Lex Fridman?

  What were some of the struggles of building up a YouTube channel? So for people who don't know, once again, if you have a YouTube channel called Everyday Astronaut and there's some incredible videos on it. So what was the, what was the, some of the challenges and the struggles in the early days?

• 3:31:14Speaker 01

  Definitely like at first, you're not going to find your own voice. And I know like even, you know, Jimmy talked to you about that, like how your first video is going to suck. You don't, you're not going to be yourself. You're going to be nervous. You're going to be, you're not going to know the tone, the pace, the, the things that are interesting. And actually originally I, I had constraints. I was really worried about making a short video because I thought there's no way anyone's going to watch a three minute video and then a seven minute video. And pretty quickly, I realized like YouTube as a whole was kind of changing. But also, there's always that historic backbone of like 22 minutes of programming for a 30 minute spot on TV. Like, no one goes over 22 or 44 minutes, you know, if you have the full hour special or whatever. Like, that is the absolute limit of what a human being can watch. You know, basically, is what I thought.

• 3:31:59Lex Fridman?

  Yeah.

• 3:32:00Speaker 01

  And slowly, I just kept playing and getting longer and actually more and more in depth into the topics. And instead of getting like pushback, you know, and being like, this is so boring. I realized as long as it's like, as I was walking people through the whole step, you know, giving them all the context they need. They're happy to get as deep into the weeds as I can get them. And so that just kind of fed the, the snowball just kept rolling. And I'm like, all right. And, you know, before you know it, I'm making hour long videos, like an hour long is, is more or less a normal length on my channel. For, for a produced video and they're really, really in depth. But I love like that process of trying to preemptively kind of guess what the questions might be. And, and, you know, part of that is like, we do like script read throughs with like our supporters.

• 3:32:43Speaker 01

  And do like cuts of videos and people, a decent amount of people see it before it goes public. And I would get those questions out of the way, you know, we get those people asking the questions. And then I, I love nothing more than trying to, you know, get all those questions answered by the end of the video.

• 3:32:58Lex Fridman?

  A question about being a, a creator on YouTube. There could be a challenging psychological aspect to it, which is like, you might invest a huge amount of your effort. Into a thing and it doesn't receive much attention at all. And, you know, there's something about YouTube and in general, social media. That makes you feel really crappy about that if you let it. If you really look at the numbers, it's very, very difficult not to pay attention to that. I mean, that's the reason why I turn off numbers on my, um, on my interface for stuff that I've created. Cause I just see it having a negative effect on your mind. But even then, you still, it still has an effect. I mean, your, uh, your epic video on.

• 3:33:44Lex Fridman?

  The the history of Soviet rockets comes to mind and we'll talk about that in a second, but it's called, people should check it out, the entire Soviet rocket engine family tree. So that's something you've researched for two years.

• 3:33:58Speaker 01

  Yeah.

• 3:33:59Lex Fridman?

  All right, you put your heart and soul into it. There's a lot of passion. There's a lot, there's a long journey. It's, and I think about like an hour and a half video.

• 3:34:08Lex Fridman?

  Is there like, is there challenges? Is there like, how difficult is that to put so much of yourself into a video and it maybe not do so well?

• 3:34:19Speaker 01

  Yeah, that that's the, that's the struggle for sure, honestly, especially as like, as we grow, I I try to make better and better videos, which means hiring more and more people to do, you know, higher end animations and spend more time editing and shooting and scripting and just, but at the end of the day, like it still can't be just losing money. And I have videos that definitely lose a lot of money because I, you know, hire 3D artists and stuff and,

• 3:34:48Speaker 01

  and I was so certain, the Soviet rocket engine video, I thought was just purely going to be a passion project. I did, I honestly was like, if it ever crosses a million, I it's a home run.

• 3:34:58Lex Fridman?

  And is it, had to see across like a couple of million now?

• 3:35:01Speaker 01

  I think it's a little over two, which is insane to me. Like, I just really thought this was more something just to put on the shelf as a resource, almost for myself, you know, like, just to kind of have that knowledge bank and something I've always wanted to straighten out in my own head and and kind of know the history a little bit better. But come to find out, like, it took a while, you know, it was a slow churn.

• 3:35:20Lex Fridman?

  Well, there's, I remember when I, when you first released it and that's when I watched it. I I remember like, this has so few views.

• 3:35:28Speaker 01

  Yeah.

• 3:35:28Lex Fridman?

  I remember being just sad. Like, I was like sad about the state of the world because I know how much love you put into it, how like, how much, I don't know, I, to me, for some reason, that somehow would directly connect to huge views. But see, you know what made me sad is like, if you use a different thumbnail or a different title, that could affect the popularity.

• 3:35:51Speaker 01

  I know.

• 3:35:51Lex Fridman?

  And then I just could imagine the torment you're going through. What if I used a different thumbnail? It's that Jimmy, the Mr. Beast.

• 3:36:00Speaker 01

  Yeah.

• 3:36:00Lex Fridman?

  Torment, like, just a slightly different title, or a slightly different.

• 3:36:06Speaker 01

  And I have videos, ironically, the last like, I don't know, five videos I've produced are horribly flopping. Like, some of my worst videos I've ever made statistically.

• 3:36:17Lex Fridman?

  The interesting one is like, the, you summarize, incredible video, you summarizing that people should go watch, about all the, the awards video for 2022, like, all the cool stuff that happened in 2022. I remember that not being that popular. There's a few ones recently that are not that popular.

• 3:36:33Speaker 01

  Like riding in a fighter jet. I thought, I thought that was gonna be easy, like, one or two million. I don't know if I've paid the flights off to go there, you know what I mean? Like, in that video.

• 3:36:43Lex Fridman?

  It makes no sense.

• 3:36:45Speaker 01

  And frankly, here's, here's, at the end of the day.

• 3:36:47Lex Fridman?

  Yeah.

• 3:36:48Speaker 01

  I, I realized, like, I have lately, especially the last like year or two, kind of disconnected from the, that aspect of it. I'm super fortunate. I have very generous, like, Patreon support and people that can help me sustain to produce.

• 3:36:59Lex Fridman?

  People go support, support Tim on Patreon.

• 3:37:03Speaker 01

  Well, it's, that, but the, as you know, as a creator, like, that is what keeps the lights on it and makes it so it, you know, I can go this deep. Like, if I didn't have that, if I had to rely solely on, like, YouTube ad revenue, I mean, I would just, it'd be super different videos. I wouldn't spend as much time researching, because I just, you know, they'd just be more glossed over. It's like a hurry to churn them out, so I can keep the machine going. And I have this incredible freedom to really dive into a topic, like, a video that I've been working on now for almost three months, is how to start a rocket engine. And let me tell you, it's not as easy as, as one might think, or I guess, as, it is as difficult as you might think. I mean, it's, it's an insane topic.

• 3:37:42Lex Fridman?

  And what do you mean by start? You mean, like, the ignition?

• 3:37:44Speaker 01

  Yeah, like, how do you physically get them running? You know, like, there's all these, you know, the valves and the, if the turbine, the turbine, you know, that we were talking about earlier, like, that has to run on the pumps, but it itself is powering the pumps. So how do you get that, like, chicken and egg? How do you get that thing started? You know, there's tons of, it's so cool. There's so many ways. And so, for me, you know, that required reading a lot and talking to people that know a lot more than me. And just really trying to make sure I understand enough of it to explain it and try to weave a narrative, you know? And so that video is three months in the making. We're still probably another two or three weeks out. And it's, I don't expect, I mean, I think this one will do relatively well, you know? But in the grand scheme of YouTube, like, still child's play, you know?

• 3:38:29Speaker 01

  But I I'm okay and I'm okay with that. I've I'm at that point, actually, where I am okay with that. It still stings and I'm more worried about just like, can I continue to do it at this quality and at this level if it's losing money? You know what I mean? So it's, there is a trade off and I am kind of having to navigate that.

• 3:38:47Lex Fridman?

  But but you have, it's sort of the depth of the impact you have is is a is a thing that YouTube can't give you numbers on, but it's it's a really important thing to sort of remember that it's really not just about the YouTube numbers or it's off for for people like you, they're basically educating and revealing the brilliance in a technology that will make humans a multi planetary species and give hope to millions of young minds that will build that future. I mean, that's immeasurable. That's not just the views. But, you know, it's, that's really

• 3:39:30Lex Fridman?

  important to sort of remember as you're creating it. That's something I I try to think about as well. So like views.

• 3:39:39Speaker 01

  Yeah, and that and that becomes more.

• 3:39:41Lex Fridman?

  Don't matter.

• 3:39:42Speaker 01

  I realize that more and more like every day, you know, the the more the channel matures, the more I realize the importance of it as an overall mission as opposed to like, you know, in the first year or two, it's a rat race of of growth and of popularity and all that kind of stuff, you know, and you feel that you feel that it's it's a driving force. These days, not so much, just because that will wear you out very quickly.

• 3:40:04Lex Fridman?

  So back to the Soviet rocket video, the epic video, probably the most epically researched video you've done. And it's like, is it, it's it's truly an epic video. So what, again, called the entire Soviet rocket engine family tree, took you two years to research. What are some fascinating things you've learned about the history of rocket engines?

• 3:40:29Lex Fridman?

  In the Soviet Union and in general, through a process of making that video.

• 3:40:35Speaker 01

  The coolest thing to me is how it's this weird blend for the Soviet Union went through a, an insane iteration process and made so many engines. Like, I didn't even touch, you know, any like maneuvering thrusters or missile engines. Like, I only really dealt with main propulsion engines on orbital rockets and there's still way too many to talk about. I mean, it's still dozens and dozens of engines. And I could have gone deeper into this, which is hilarious. They iterated so much, made a new engine for, just at the drop of a hat, yet they still also like did super primitive things. You know, they, they physically are still today lighting the main combustion chambers of the Soyuz engines of the RD-107

• 3:41:19Speaker 01

  and RD-108 with essentially matchsticks. Like, they'd literally stick a T-shaped thing up into the chamber and have a pyrotechnic in it that ignites the actual propellants in the combustion chamber. It's not the most elegant solution in the world. They're still using that. So they went from like, the whole spectrum of like, it's a mixture of like, make it better, faster, harder, stronger, gooder, all the way around, to also if it ain't broke, don't fix it. It's like, it employs all of the above.

• 3:41:48Lex Fridman?

  So it's like, it's a lot of innovation, but also they use duct tape. So it's like all of it together.

• 3:41:55Speaker 01

  Yes, that's exactly like, that's exactly the way to put it. And they did things that are insane. They developed a full flow stage combustion cycle engine. This engine, had it been used, I mean, it would have put the F, it was same relative size as the F1 engine on the Saturn V, like, in that same category, way up there of like, you know, 6.7, like, meganeutrons of thrust or something around, and then the F1 is like 7 or something. It's huge.

• 3:42:21Speaker 01

  Yet way more complicated, way more efficient, way just better engine in that sense. As far as far as performance goes, yet it never flew. It never left the stand, you know, they they'd never built the rocket around it. The N one, which was the, you know, the most powerful rocket to have flown so far to date. Like it never made it through its first stage burn. And all four attempts failed spectacularly and yet it had so much technology on it that was still unrivaled today almost like finally now we're beating it. The NK thirty three is that they developed for that rocket like finally today. We're to the point of like having better engines than they built in the sixties.

• 3:43:01Lex Fridman?

  Yeah, what stands out to you from the N one family of rocket engines?

• 3:43:06Speaker 01

  Well, it's interesting because the N one was the Kudsnetsov Design Bureau. And he was actually an aircraft manufacturer. So he was one of the first people outside of kind of the the missile and rocket program. You know, he had all these other bigwigs kind of in the other OKBs that were developing missiles and rockets. And then all of a sudden here comes Nikolai Kudsnetsov, who had never developed a rocket engine. And so his first attempt at rocket engines was the NK series, NK fifteen, NK thirty three. And they were amazing. They were brilliant. There are these wonderful closed cycle oxygen rich engines that were that were awesome. They were awesome engines and that were, you know, because I love that because he his

• 3:43:47Speaker 01

  direct boss, he since he wasn't necessarily in the in the aerospace, you know, or in the, I guess, the rocket missile defense world. He didn't have to at the fall of the Soviet Union, he didn't have to give away all of his things to the same people as the other people. So he hid, you know, like 80 of his engines in a hangar. And and then we still literally use them in the United States. We used altogether, I think it was like eight or 10 of them. Repurposed them as they're called AJ twenty sixes in the United States, but like we still were flying Soviet rocket engines in the 2000s because they were better than engines we are building today.

• 3:44:27Speaker 01

  Like that's to me, that's my favorite fact about the N one rocket is that they're still that good, that that they were the the best choice for at the time orbital sciences.

• 3:44:38Lex Fridman?

  Some of the culture that engineering has led to these things that still work. It's incredible.

• 3:44:45Speaker 01

  Yeah.

• 3:44:46Lex Fridman?

  You said that the RD one seventy one is one of the coolest engines ever made. Why is that?

• 3:44:51Speaker 01

  Yeah. So one of the fun things about the Soviet engines is it'll look like a lot of their engines look like multiple engines because you see multiple nozzles. You see multiple combustion chambers and you would think, well, obviously, you know, the nozzle is the engine, right? But what they actually would do, the real, the real heart and the real power of the rocket engine actually comes from the turbopumps, comes from the pumps themselves. And, you know, as we talked about earlier, that that includes the turbine and the, in the actual pumps that flow the propellant into the, into the chambers. And so the Soviet Union was incredible at developing these closed cycle, high-powered turbopumps. But if you try to scale the combustion

• 3:45:32Speaker 01

  chamber too big, you end up with what's called combustion instability. You're, you're having, you have such a large surface area of crazy flames, you know, and combustion happening, they can get these weird pockets and oscillations and frequencies and, and they just couldn't make big combustion chambers. They never figured it out. They never quite, well, they, they did actually kind of figure it out, but they, they didn't like it. So they ended up just shrinking down and having small combustion chambers and just sending, splitting the pipes, basically, instead of one fuel pump going into, or one pipe going into one combustion chamber and one oxidizer pipe going into one combustion chamber, they'd split it off into two or four engine, into two or four combustion chambers and kind of spread that workaround so they

• 3:46:16Speaker 01

  didn't experience this combustion instability. So the RD-171 is like, still to date, the most powerful rocket engine ever built. The turbopump is insane. I don't even remember how many, you know, like 200,000 horsepower or something comes out of that turbopump in order to flow the amount of propellant necessary at those rates and at those pressures into the combustion chamber. So it has four chambers and it's just, it's just an absolute marvel of engineering. And, yeah, and then the cool thing too is specifically with the RD-171, its engine, all four of those nozzles can actually pivot and, and rotate. And I just now, as I'm explaining this, realized that has to mean that they have

• 3:46:58Speaker 01

  Joints, like flexible joints in the high pressure pump lines in order to like I never I'm this is the realization I'm having right now because normally you put the gimbal above the turbo pump like the the the mount where the engine swivels so that you have low pressure coming from the tanks into the pumps and then you just have a straight you know fixed pipe flowing into the engine so you don't have to bend that pipe and have it be dynamic if they had the four chambers moving independently from each other that means those four chambers all had to have a flexible high pressure pipe going which I don't even I don't know if that's why am I just now realizing this?

• 3:47:36Lex Fridman?

  Yeah, so there's engineering challenges with that.

• 3:47:39Speaker 01

  Insane. I I never even thought that was a thing you would ever could do honestly. I would I gotta look into why and how and what.

• 3:47:46Lex Fridman?

  Yeah, I wonder why that the design decision was made.

• 3:47:49Speaker 01

  So the easier thing to do normally is you would keep those nozzles fixed and then a fixed like say the the Soyuz engine, the RD 107 and 108, they have a fixed main combustion chambers and they and they use these little Vernier or some people got mad at me for saying Vernier and Werner engines that swivel themselves and those provide your your control authority so that the main chambers stay fixed and then you get your your roll and your pitch and your yaw out of auxiliary thrusters.

• 3:48:14Lex Fridman?

  By the way, did you get anything wrong in that video that people told you about?

• 3:48:18Speaker 01

  Yeah, I a few things. Yep. First off, we had a graphic error where we actually were we you know, we copied and pasted a lot of our like After Effects projects. So our nuclear engines, one of them on screen says that it runs on RP1. It does not. It has basically all the wrong stats. We just didn't catch it in the edit, you know, that we literally copy and paste it and I say it right on screen, but the like in the voiceover, but on screen it's wrong. The other thing, and I'm excited to ask you about this.

• 3:48:43Lex Fridman?

  Uh oh.

• 3:48:44Speaker 01

  I watched and I spoke with a lot of Russian speaking individuals. We had a lot of research assistants that were reading and blah blah. I tried really hard to learn how to pronounce Sergey Kurelio's name.

• 3:48:58Speaker 01

  And I'm still gonna say it wrong no matter what, but I my understanding.

• 3:49:01Lex Fridman?

  Yes.

• 3:49:01Speaker 01

  And from listening to native speakers is closer to Kurelio than it is Korlev.

• 3:49:07Lex Fridman?

  Yeah, definitely. Sergey Pavlovich Kurelio.

• 3:49:11Speaker 01

  See, I will never say it that perfectly, but I know it's not just Korlev. I mean, again, the the English translation of it likely I should have just said Korlev and said I'm saying it the dumb America way, but. But you rolled your R. Comrade.

• 3:49:27Lex Fridman?

  Okay, excellent. So, uh, let me just ask you in a difference in, in the culture, because you've researched so many rockets from so many different eras, the Saturn V and just everything you're seeing now. Are there some interesting differences, especially when you look at the space race, between the Soviet rocket engineers and efforts versus the American?

• 3:49:54Speaker 01

  There's, I mean, there's definitely huge, huge cultural changes. And the fun thing is that they kind of spawned from the same, they have the same starting place. Both, you know, Soviet rocket engines and Americans all came from the Nazi V2 rocket and the A4 engine. Literally physically spawned from that because at the fall of, you know, at the end of World War II, we took a handful of German scientists and the Soviets took a handful of German scientists. And they both got their own a little bit, some blueprints here and there, and the others got some blueprints. So we literally have the same, it's a weird thing where we're starting from the same like thing and letting two, uh, two divergent, you know, divergent paths go crazy on their own development. So it's really fun to see the cultural differences. One of the things the United States did is they really would

• 3:50:38Speaker 01

  kind of take an engine and, and just perfect it more or less and then, and not really evolve that much. Like they, they, I don't know, and I don't know why. I actually need to do a history lesson on all of the US engines, but it's literally like, as far as orbital class engines before now, I mean, it's like a dozen or two, you know, it's, it's, it's a tenth the amount of the Soviets. And the Soviets just literally made up a new engine every time they had a new, like, they wouldn't, uh, and it was like a completely different engine.

• 3:51:11Lex Fridman?

  Yeah.

• 3:51:12Speaker 01

  So I just, yeah.

• 3:51:13Lex Fridman?

  I wonder if there's some aspect to the culture, and I don't want to overstate it, but there is more of a safety culture, I think, in the United States. And I think if you care about safety, or rather, like, you have

• 3:51:27Lex Fridman?

  You're more risk averse.

• 3:51:29Speaker 01

  Yeah.

• 3:51:29Lex Fridman?

  So you care about safety more, about the value of human life and the risk taken there. That you will iterate less.

• 3:51:36Speaker 01

  So yeah.

• 3:51:37Lex Fridman?

  I think the Soviets, especially in the early aspect of the program, I don't want to overstate this is. Some of it is just through stories, you just hear anecdotes. They're more willing to take risks.

• 3:51:49Speaker 01

  Yeah.

• 3:51:50Lex Fridman?

  Risks with human life, risks with spacecraft.

• 3:51:52Speaker 01

  For example, the first orbital space flights from the Soviet Union, the the cosmonaut had to eject out of the capsule and parachute to a landing.

• 3:52:01Lex Fridman?

  Yes.

• 3:52:01Speaker 01

  That's not very well like known. And it wasn't, they hid that even from history as best they could at first, because they were slightly ashamed that they couldn't have a full recovery system with their spacecraft. They could physically recover it, but they wouldn't have been able to recover the cosmonaut in one piece. So instead they had them just eject out of the thing and parachute to safety like. That's insane. And so there definitely was some some extra risks and. But also a freedom to just like push things to the limits and try everything. You know, they threw all the spaghetti on the wall.

• 3:52:33Lex Fridman?

  It's funny that most people probably don't even know the first person in the space in America. And obviously, everybody knows that in the it's like.

• 3:52:43Lex Fridman?

  It's it's kind of interesting how the space race and even World War Two. Even like the history books, you ask most Americans. They think that America won World War Two. Like without America, like they the the real heroes of World War Two is America. You ask British people, they say, and and everybody has a pretty good justification. Like without Britain, without Churchill, their Hitler would have taken over the world. And I think probably the strongest case is the Soviet Union case, that they're the ones that won the war. The reason it's the strongest case is where most of the fighting happened.

• 3:53:27Speaker 01

  Right.

• 3:53:27Lex Fridman?

  Most of the death happened.

• 3:53:29Speaker 01

  Yeah.

• 3:53:29Lex Fridman?

  Most of like, most of the destruction, but everyone has their perspective. And certainly in the space race, you know, the great accomplishment is the first man on the moon. From the US perspective.

• 3:53:39Speaker 01

  Yeah, I was gonna say.

• 3:53:40Lex Fridman?

  And then Yuri Gagarin, from the Russian perspective, is the first man in space. And that, I think, still persists. And some of that, in healthy forms, is probably constructive to a little bit of competition, is pushes all the, all the great scientists on the east side. But, you know, what do you think about this Yuri Gagarin mission of the first human in space? And the Vostok mission in 1961? Just in general, when you, when you look back at that time, leading to the, the, the first man on the moon?

• 3:54:13Speaker 01

  Yeah, April 12th, 1961, Yuri's night, baby. That's a, yeah, it's, it's insane. What's insane to me is, is the first person in space didn't just go to space, he went into orbit. You know, Yuri Gagarin flew around the earth in orbit and re-entered. That's a monumental task compared to suborbital. So the United States did two suborbital flights in that same year, I believe in that same year, at least, I'm pretty sure, in 1961. They flew for the first time orbitally in 1962. So they weren't terribly far behind to get a human into orbit. Like, in the grand scheme of things, you know, 10 months difference. But at the same time, like, the fact that Soviet Union just went straight to flying someone into orbit is monumental.

• 3:54:55Lex Fridman?

  And I'm sure they did not do excessive, rigorous testing here. Because there is a space race, and you have the first is important. Just imagine being Yuri.

• 3:55:08Lex Fridman?

  What do you say when they're like launching him, like, let's go, or something? Like, uh, I mean, you're taking, uh, we're talking about you being on Starship. Like, you're taking a pretty big risk being launched out into orbit.

• 3:55:21Speaker 01

  Oh, hopefully, a lot less risk than what Yuri went through. So Yuri's, Yuri, the crazy thing, remember those matchsticks we talked about?

• 3:55:29Lex Fridman?

  Yeah.

• 3:55:30Speaker 01

  You know, there's, there's 20 main combustion chambers on Soyuz, and there's four, and 12 more Vernier engines that all need to be lit. So you're riding, you're sitting on top of this, this booster, and they light all of those, 32 combustion chambers on the ground, and then it has this insane separation process between what the Soviet Union would call the first stage and the second stages, but we would call it like the core stage and the boosters. They all, four of these boosters have to peel away perfectly from the core stage simultaneously. You know, if one of them sticks on, mission failed. If one of them doesn't eject properly and drags into the other tank, you know, you're, it's, it's, it's a goner. So the, the staging process of, of the Soyuz is, is insane to me that, that that ended up

• 3:56:15Speaker 01

  working out. I, I was just, the, the technology in Soyuz, and I mean, more or less, that same rocket is what's still flying humans that are cosmonauts from, you know, Roscosmos and going to the International Space Station are flying on a variant of that Soyuz rocket still today. It's still like that big of a workhorse.

• 3:56:38Lex Fridman?

  What do you think about Roscosmos as it stands today? Its history and its future in comparison to NASA and other national efforts? And in comparison to commercial space life?

• 3:56:52Speaker 01

  Yeah. I mean, utmost respect for the engineers involved and, and everything that's happened. I think Nergomash is like still some of the, one of the greatest engine manufacturers when they have the funding to do so, but man, it seems like they're, they're falling from grace as far as space prowess, you know, the Roscosmos went from having, I think they got very comfortable at the top of, you know, from 2011 until 2000, until 2022 or until 2020, they were the only ride to the International Space Station. Since then, like in, it started, I feel like in 2018, honestly, I think that's kind of when things, that's the first time I specifically remember a pretty nasty like thing happened in 2018. I think it was a Soyuz mission to the International Space Station had one of

• 3:57:35Speaker 01

  the boosters not detached and had to have an abort. But, you know, that, that happened, then all of a sudden, next thing you know, there's a progress being docked to the ISS a couple of years ago that spun the ISS, cartwheeled the ISS out of control, followed a few months later, the Piers module docks to the International Space Station, spirals the International Space Station out of control again with like a thruster getting fixed on. There's a whole In in a Russian segment, there's, well, I think the most recent one right now, there's a Soyuz docked to the ISS that has a puncture in it and it's leaking coolant. And will not be returning humans on it. So they're actually having to fly up an uncrewed Soyuz.

• 3:58:13Speaker 01

  And that one likely wasn't a manufacturing error. It probably was like a micrometeorite puncture, rendering spacecraft unusable. We don't know for sure yet. But it's just really been like this fall from grace where they have, they have all the potential, potentially have some of the best engines, some of the the best rockets and especially like right before the collapse of the Soviet Union, the Brawn Shuttle and the Energia rocket were incredible. Had they been able to evolve that into Brawn 2 and the reusable Energia, they had a fully reusable Energia on the drawing board and like, I honestly, fully think they could have done it.

• 3:58:51Lex Fridman?

  Is it possible to return to a place where there is friendly competition between nations that ultimately

• 3:58:58Lex Fridman?

  unites and inspires the peoples of these different worlds, these very different worlds that have especially recently come to conflict over the, over the war in Ukraine, the tension builds.

• 3:59:11Lex Fridman?

  The war, the conflict, the suffering is actually creating more and more division, creating more and more hate. I think as we've talked about, I think science and engineering and especially the most epic version of engineering, which is rocketry and space travel unites people, unites people even in a time of tension, conflict and war. So do you have a hope that we can return to that place?

• 3:59:36Speaker 01

  I think historically, spaceflight has been one of the most bonding things. You know, we look at, we have countless examples of, you know, Cold War enemies coming together and working together, lending a hand. Apollo 13, for example, of course, you know, there is the potential that who knew where it's going to reenter since it is not in the plane trajectory at all for reentry. And the Soviet Union said, hey, wherever, you know, wherever they land, like we'll help you guys out basically, you know, and that was a pretty big thing at the time, obviously. We also in 1975 saw the Apollo Soyuz mission, which was Apollo spacecraft docking with Soyuz spacecraft. First time there's international collaboration. And again, 1975, still very amidst the Cold War.

• 4:00:21Speaker 01

  Yet we have this collaboration that I don't know what else could have done that. You know, I mean, and think about what it actually takes to do that. You have to come up with a docking module that is, you know, like that takes the two different air environments and the two different docking systems and talk to the engineers and mission planners and figure out, you know, train together, the cosmonauts and the astronauts trained together and got to know each other. They were crossing boundaries and borders and coming together for this mission. And even if it was totally a fluff piece, like even if it was totally this like, you know, cynical, you know, just trying to make a pretty face for everybody, for the, for the cameras or something, obviously it still had an impact.

• 4:01:01Lex Fridman?

  Yeah, the symbolic impact, but there's also the practical impact. I mean, a lot of people have to work together.

• 4:01:07Speaker 01

  Yes.

• 4:01:07Lex Fridman?

  And that, and that has a ripple effect on the culture, on the different engineers.

• 4:01:13Speaker 01

  A hundred percent. And even just the astronauts and the cosmonauts involved, like, think about what, what probably went through their heads during this process of like, going from, oh my God, I'm going to have to work with them to getting to know them and then sharing meals in space. Like, that's a crazy transformation of timelines. And I would love, I, I do think that spaceflight has the, the ability to, to bond us and unite us because it is ultimately, you know, this little tiny little planet we're floating around on, you know, it's the only, it is the boundary that we all share, you know? You only can, it only takes you getting off this planet to realize, oh my God, we're all neighbors. We're all living in the same house together.

• 4:01:53Speaker 01

  And I, I do think ultimately, you know, as we continue to expand our horizons and expand our exploration, that it has the potential to unite us more than, than it has the potential to divide us.

• 4:02:06Lex Fridman?

  So one of the potential conflicts of the 21st century that I think everyone wants to avoid, both in the cyberspace and in the hot war space, Cold War, hot war, all kinds of war, all kinds of economic conflict, this was between the United States and China. So China is going full steam ahead in developing a space program, doing a lot of incredible work. Like you mentioned, 64 launches in 2022 with two failures.

• 4:02:39Lex Fridman?

  But, you know, moving straight ahead.

• 4:02:42Speaker 01

  And by the way, those failures, we had a lot of startups, like a lot of the launches were from brand new companies. So to have two failures out of 64, I mean, that's still impressive. If you look at operational launches, it was flawless.

• 4:02:55Lex Fridman?

  Do you see a pathway where there's, again, in that same way, collaboration or friendly competition between all the different companies and nations in the United States and China in the, in the next, as we push towards the moon, Mars and beyond?

• 4:03:16Speaker 01

  I held a dumb hope that China would actually be allowed to sign on to the Artemis Accord to be able to take part in this next step towards the moon. I mean, just imagine if like, if they provided a, you know, a propulsion module or a lander or something and we actually came together to land on the moon instead of having another space race, you know? It's like, it would have been so cool. And yeah, I still am hopeful that similar to, to back in the Cold War, that we might have something like that someday where we actually are collaborating. And it feels like sometimes we're really close to that. And then other times it feels like we're really far from that. And it just sucks because I know, and you know, I try really hard on my channel to, to always separate and celebrate the

• 4:04:00Speaker 01

  work being done, you know? Because at the end of the day, there's someone that's just going home to their family, clocking in hours, working really hard on, on pushing their program and, and doing engineering work, you know? And it's, we don't get to choose where we're born and what we're born into. So I really like to avoid, you know, the, the political aspects of things and the geopolitical aspects and just appreciate the science and the, the science we're seeing and the, the progress that China's doing in the last 10 years is, is very akin to, you know, early spaceflight programs and, and with the runway of like, just go, keep on going. Like, I see no reason for them to be slowing down. So it's, it's definitely something to watch and, and be interested in. And who knows? I mean, there really genuinely might be a race to the moon again, and there really

• 4:04:45Speaker 01

  genuinely might be a race to Mars.

• 4:04:48Lex Fridman?

  The part of me is excited about that because a race is pretty cool.

• 4:04:53Speaker 01

  Yeah.

• 4:04:55Lex Fridman?

  But hopefully it's friendly competition and some collaboration. It is true that maybe I'm being a bit cynical, but nations sometimes, governments and leaders of those governments sometimes ruin things. Like you don't often have, statistically speaking, it's harder to have a leader of a nation that looks beyond the political, the particular political bickering of that nation. And you have like a JFK type character that really steps up and inspires. I think statistically speaking, it's better to have somebody like Elon, who's a leader of a company, like a commercial effort, that is able to look beyond the borders of nations.

• 4:05:36Lex Fridman?

  And certainly inspiring educators like yourself to look beyond the borders of those nations and the geopolitical conflicts and so on, to inspire people. I think that's just made so much easier. Like you can have more reach. Tim Dodd can have more reach than NASA, right? Like in terms of inspiring the world. And that's fascinating. Like that gives power to the individuals that see past the silly, short-term geopolitical conflicts.

• 4:06:11Speaker 01

  Yeah.

• 4:06:12Lex Fridman?

  That's the hope at least.

• 4:06:13Speaker 01

  Yeah.

• 4:06:14Lex Fridman?

  Do you worry that there might be a war in space?

• 4:06:18Speaker 01

  Yeah.

• 4:06:19Lex Fridman?

  Let's look out into the future. So forget, so the interesting thing about these rockets, right? Let's not forget rockets do what rockets do, that they can carry payloads that can be weapons. Do you worry about this?

• 4:06:37Speaker 01

  I worry most about space wars as leading to the Kessler syndrome of having a cascading effect of like a spacecraft blowing up and then affecting another spacecraft and that blows up. And then all of a sudden you're trapped and have this debris cloud that we can't. You know, go, we can't go into space anymore. Like, that's my biggest, because frankly, at this point, we could annihilate ourselves with terrestrial stuff anyway. You know what I mean? We don't need space to, to, to end society as we know it. You know what I mean?

• 4:07:08Lex Fridman?

  Yeah.

• 4:07:09Speaker 01

  But we do, we could really, and the, the good thing is, I think everyone, well, mostly everyone seems to understand this for the most part, that like, we really can't be risking blowing up stuff in space in, in low earth orbit, because it could easily, like, we could strain ourselves from space assets for 50 years.

• 4:07:29Lex Fridman?

  If, oh, can you elaborate on this? So like, what is the danger of the debris there that could jeopardize?

• 4:07:35Speaker 01

  Yeah.

• 4:07:36Lex Fridman?

  Access to space?

• 4:07:36Speaker 01

  So, for instance, and it was only a couple of years ago, Russia did a, an anti-satellite test on a, on an orbital, there's a, we've done this, the US has done this, like, I'm not pinning it on them, but we kind of know nowadays, like, don't do anti-satellite tests on orbital things, because those things stay in orbit. You know, when you blow something up in space, it's not like, you know, people think, you know, when, in, in space, like, oh, you throw a, a something, it's just going to keep going forever and ever and ever.

• 4:08:03Lex Fridman?

  Yeah.

• 4:08:04Speaker 01

  I mean, that's, in the, in the sense that it's not going to be slowed down due to, you know, due to air resistance, it's going to continue to do that, but it's staying in orbit around the earth. Like, you just slightly change the orbit of it around earth when you throw a ball or something, you know? So, the scary thing is, when you blow up a satellite, all those pieces of that satellite are now millions of bullets in a halo around the earth, in a very specific halo, you know? So, some things get blown up faster, you know, in, according to its orbit, faster, so they'll go a little bit higher elliptically, some things will get slowed down in that explosion and actually re-enter. Some things will go sideways and change its inclination of that orbit.

• 4:08:46Speaker 01

  So you have this debris field, but it more or less becomes a band of like, no, no, you know, like a big scary, sharp scary bullets that can destroy another spacecraft. And so then all of a sudden, especially now Starlink, and we're talking about thousands and thousands and thousands of satellites in space, if all of a sudden, one, you know, a couple of them crash and, and, you know, blow up, and all of a sudden you have all the shrapnel going everywhere, and then that hits another satellite, that creates shrapnel, you can literally blanket our entire low earth orbit in 17,500 mile an hour bullets.

• 4:09:22Speaker 01

  You know, we're talking that the kinetic, the kinetic energy in this is so hard for people to fathom because that, you know, that's over 10 times faster than most like rifle bullets. And even like a big 50 cal is not going to be, you know, we're still talking about about 10%. That so when you think about the kinetic energy, it's insane. So a fleck of paint can go through panes of glass at that velocity, you know, a little piece of metal can puncture, you know, blow straight through.

• 4:09:52Lex Fridman?

  So like, so are actions that seem small, so small scale military actions can have,

• 4:10:02Lex Fridman?

  can have dire detrimental effects to the whole space program, like global space program.

• 4:10:07Speaker 01

  Oh, yeah, it can affect everything and everyone.

• 4:10:10Lex Fridman?

  Including the like, including satellites.

• 4:10:13Speaker 01

  Oh, yeah, especially satellites. Like that's the, well, I mean, the, the good and the bad thing is, the good thing is, a lot of satellites don't operate in low earth orbit. Like a lot of the ones that we use day to day, a lot of them are in medium earth orbit, like their GPS or their geostationary, which are way, way, way out there. And because of that, they, they won't really ever de-orbit, or like it'll take, you know, millennia to de-orbit because the, you know, just because something's in space doesn't mean it's, it's there forever, especially like in low earth orbit. The atmosphere doesn't just suddenly stop. It's not like you hit the Karman line 100 kilometers and all of a sudden there's zero atmosphere. The atmosphere just slowly tapers, you know, you can experience that yourself as you climb a mountain, you slowly realize there's less

• 4:10:54Speaker 01

  and less air, you just keep going. And just because you're in space 200, 300 kilometers up, there's still trace molecules, you know, there's the occasional oxygen molecule, there's the occasional nitrogen molecule. And so that is actually drag. So as a spacecraft in low earth orbit, depending on its altitude, will take anywhere from five years to five months to de-orbit, you know, or two months or one month, like depending on its orbit or its altitude, will have some parasitic drags still and slowly throughout time slow down, which lowers its orbit, which drags it down more, lowers its orbit, and et cetera, et cetera, until it re-enters. So if we end up with some kind of catastrophic event where

• 4:11:35Speaker 01

  the entire low earth orbit is, you know, has been inundated and blown up, it'll take months for the first band, you know, to clear up. It'll take years for something like beyond, there's charts, you know, people have all this stuff available. You shouldn't look it up.

• 4:11:48Lex Fridman?

  It's terrifying, by the way.

• 4:11:50Speaker 01

  But

• 4:11:51Lex Fridman?

  This is really

• 4:11:52Speaker 01

  The but again, the caveat is for the most part, the lower Earth orbit stuff would clear up within years. So we could get back to doing some more with it like Starlink stuff would probably be able to be re and you know, we could kind of redo it and build up from the ground up again. GPS wouldn't be wiped out and our geostationary satellites wouldn't be wiped out. But the scary thing is we wouldn't be able to relaunch and replace new things because we're stuck. We were not going to fly through that debris field, you know?

• 4:12:19Lex Fridman?

  And we avoid that by avoiding military actions in space.

• 4:12:22Speaker 01

  And these days, like, there's more and more requirements and legislation and especially trying to get international collaboration on having end of life plans for satellites. So that satellites, especially those in low Earth orbit, have like drag devices to increase them. Once they're done, they literally pull like even just a ribbon, like a silly little like, you know, 40 foot long ribbon will sit there and it'll slowly, or it can speed up its reentry process by months or years or whatever. So we're starting to see that this is now an importance. There's a really cool company called Stoke Aerospace out in Washington is one of these launch provisor providers that's really looking not into just trying to be the next, you know, SpaceX launch company.

• 4:13:02Speaker 01

  They're really seeing satellite, bringing stuff down from space is actually being, especially right now, we have all of these hundreds and thousands of satellites being launched every year. Someone at some point is probably going to have to do some cleanup. And so they're looking at being one of those companies to do that.

• 4:13:20Lex Fridman?

  Well, what do you think about Starlink? And the efforts of Starlink to put a very large number of satellites out there and provide internet access to to

• 4:13:34Speaker 01

  Anyone.

• 4:13:35Lex Fridman?

  To anyone.

• 4:13:36Speaker 01

  Generally, I think Starlink is phenomenal. And I would be saying this if it was any company, I want to make that clear that people think I'm just some, you know, SpaceX fanboy or something and anything they do is perfect.

• 4:13:47Lex Fridman?

  I think I think as you're a fan, I could say you're basically a fan, a fanboy or just a fan of everybody that's doing space stuff. And I don't like, there's no, even in this whole conversation, there's no way we cover like 10% of what I want. To talk to you about, so we're jumping around. I mean, there's, we could talk probably for now, uh, an hour about Artemis. Uh, we could, we could talk about anything with ULA, obviously, the, all the other, all the other commercial efforts. We could talk about the NASA efforts that, you know, the, I mean,

• 4:14:17Speaker 01

  Yeah.

• 4:14:17Lex Fridman?

  And Saturn five, like, are we gonna really go with this conversation, not talk about Saturn five? And we might, okay? So like, anyway,

• 4:14:24Speaker 01

  Starling.

• 4:14:25Lex Fridman?

  Fan of everything. Starlink is in general exciting to you.

• 4:14:29Speaker 01

  And not for the space assets, but just the potential for humanity. Like, I, I really think even as a consumer of the internet, personally, that what our studio space down in Texas, we're stuck with, with MediaCom, which has like the least reliable internet service, period. That's the only option. Either that or they're trying to charge me like $20,000 to run a fiber optic cable, like a thousand meters or something like it's, it's insane. I'm not going to do that. I bought Starlink. It helps, but it's still not, you know, amazing, but it has, you can see where this is going in a year, two, three, five years. Like, oh, I can totally screw this other internet provider. And this is now by far the best option. And it's available literally anywhere. You don't have to be limited to your internet, local internet service provider.

• 4:15:14Speaker 01

  And, and on the global scale, of course, you have, you know, people being able to learn and learn about rockets, learn about, uh, water management and architecture and city planning and fitness and health. All of the, all of the modern conveniences that we Google every single day, there's people that don't have access to that right now. You know, I, I'm a self-taught rocket nerd. I would not be who I am if it wasn't for the internet in the last seven years, you know, six, seven years.

• 4:15:41Lex Fridman?

  So unlocking the intellectual potential of places like Africa, of rural areas that don't currently have internet access.

• 4:15:50Speaker 01

  That's a genuine, that's a huge thing. That's like humanitarian 101 is give people access to information. And you like, you know, I think we have this, uh, potential to try to step in and, and fix other people's problems. But the reality is like, people are smart. No matter where you are, you give them the resources to learn, they're going to solve problems. They're going to problem solve. They're going to engineer, they're going to, but if you don't give them access to that information, they're going to be stuck in their, in their cycles, you know? And so I, I think the potential for Starlink is incredible. I think it's already impactful. It's already affecting. People in rural and indigenous areas and it's already affecting businesses and all

• 4:16:30Speaker 01

  that stuff. I think it's great. I think it is, you know, there's some downsides with astronomy, with ground-based astronomy that it can hinder observations from the ground. There's already a lot of communications between SpaceX and astronomical societies and things like that because it is a real concern. You know, it's, it can ruin observations, it can ruin data. But like one of the big ones, for instance, recently, I think a new thing they're going to be working into is that currently if a Starlink is flying over, over a ground-based asset, a lot of, a lot of ground telescopes actually have a laser that goes up and it measures the atmospheric distortion and the telescopes literally sit there and like

• 4:17:15Speaker 01

  by the millisecond fixes, like changes the focus and fixes those atmospheric distortions. And that laser can interfere with satellites. So previously, I'm pretty sure that SpaceX actually had to, you know, request that as they're flying over these satellites, they are these telescopes, they turn off the laser. And when you have tens of thousands of these things flying, it's, you're going to be turning off the laser more than it's on, you know, and just being this insanely inconvenient thing because you're going to have these junctions happen often. And I think one of the things that SpaceX is like, okay, no, no, no, you guys keep the laser on, we'll deal with your laser. Good, good step, you know, things like that, mitigating the brightness of them so they're not visible under most

• 4:17:58Speaker 01

  conditions, of course, like there's still always going to be visible in some. But then ultimately for me, it's like this, you have this weird, like almost like a puberty of spaceflight and astronomy where currently it's not cheap enough to really do a ton of incredible science or space-based telescopes. You know, we have Webb, we have Hubble, we have, you know, all these other, you know, awesome space-based telescopes, Chandra, you know, et cetera, et cetera, whatever. You uh, but it's still so expensive to launch them.

• 4:18:32Lex Fridman?

  Yeah.

• 4:18:32Speaker 01

  That we're still so reliant on our ground telescopes. But in the future, you can see a world where, oh, this is so cheap. We'll just launch like, we can launch 50 James Webb Space Telescope sized telescopes this year for half the price of doing it on Earth, you know, and get way better data. So in the future, I think in 20, 30 years, we'll look at it and be like, oh, man, that was an awkward time where space assets were interfering with astronomy. But I think in the future, it's like, can you imagine doing space, you know, astronomy from the ground? That's insane, you know?

• 4:19:02Lex Fridman?

  There could be complexities to just having that many, uh, just another topic. So a complexity is associated with having so many satellites, uh, especially with competing companies and competing nations. Do you see that as an issue, having tens of thousands, hundreds of thousands of satellites?

• 4:19:18Speaker 01

  Yeah.

• 4:19:18Lex Fridman?

  It becomes a very interesting robotics collision avoidance problem.

• 4:19:23Speaker 01

  The, the one thing to keep in mind is perspective. Like I know 10,000 satellites and 20,000 and 100,000 satellites. Sounds insane and it sounds really scary. But I mean, just even look at how many planes are in the air at any given time. And the planes are, are bigger. They're flying slower, which actually means there's a greater chance of collision. If you think about, you know, two objects occupying space, if they're, one's moving really fast, like imagine trying to, you know, throw two basketballs at each other relatively easy. Now try shooting two bullets at each other and having like, you know, at 90 degrees from each other. You have to have your timing down like really perfect to do that. Now take that times 10, you know, and these objects are taking up a physical space very small amount of time.

• 4:20:04Speaker 01

  They're relatively small, like most satellites are not very big and they have limitless altitudes to deal with. So even though you can have what look like convergences, you know, they can be 10, 20, 50, 100 kilometers difference often. And, and you know, they're, they're dealing with this. Like all the, the, all space assets know, hey, I'm at this orbital plane and this blah, blah, blah, blah. And they know their altitudes and know their safe distances and have these margins built in and it's space. So there's like an insane amount of room, you know? So there's.

• 4:20:32Lex Fridman?

  There's a lot of margin.

• 4:20:33Speaker 01

  There's a lot of margin, but of course you can't excuse that all the way. Like you have to still have plans and, and be considering that and considering collisions and considering all of the above.

• 4:20:48Lex Fridman?

  When do you think the first human being will step foot on Mars?

• 4:20:53Lex Fridman?

  You don't like timelines, but is this something, and you're very much focused on kind of the short term of incredible progress that's happening, and that makes total sense. But there is the Mars plan that was at the origin of the commercial spaceflight efforts. Do you still see and dream about that day?

• 4:21:15Speaker 01

  Let me be clear that I don't want to go to Mars. But I do think if you're, if you're making me guess a timeline for when humans will walk on Mars. I even a year ago, I still would have said by the end of 2020, like the 2020s decade, you know? So by December 31st, 2029, I thought humans would have walked on Mars. I'm starting to think

• 4:21:39Speaker 01

  that's still too optimistic, but I do, I, I definitely think by 2040. Like I, I for sure think that, and I really think it's, it's just hard to predict that curve, you know, that, that project out that curve. We're going to go from feeling like it's impossible to like it's feeling like it's inevitable.

• 4:21:55Lex Fridman?

  You know, it could be another by the end of this decade JFK type moment, especially if China steps up with the space race. It could be like, all right, NASA, NASA kind of says, all right, this Elon fellow like really make this a gigantic effort.

• 4:22:10Speaker 01

  Well, and if Starship works out as planned and as, as NASA has invested in human landing system, they're relying on SpaceX to land on the moon. SpaceX can land on the moon, they can land on Mars. Now, whether or not the life support and the human considerations of, of long-term spaceflight missions and high radiation and blah, blah, blah, blah. Refueling on Mars is a huge, huge, huge deal. They definitely could send a Starship to Mars and land, ideally land in one piece on Mars.

• 4:22:39Speaker 01

  As soon as they can land on the moon, they can land on Mars, basically. I mean, those two things are very, in some ways Mars is almost easier. If you can use, because you can use the atmosphere to slow down. It actually doesn't take that much more delta V to actually land on Mars than it does. Because on the moon, you don't have any, you have to first get out to the moon, then orbit the moon. You know, it's a slowdown. Every one of those is a maneuver change. Then you have to lower your orbit until it coincides, you know, hits the moon. And then it's a slowdown enough to not explode when you hit the moon. So there's a lot of delta V there, a lot of change in velocity. Mars is actually, by the time we kind of crunch the numbers, it's relatively similar. It's just a lot more difficult, like timeline wise and, you know, accuracy and all of these other communication. You know, there's a lot of other things obviously involved.

• 4:23:25Speaker 01

  I'm glossing over it, making it sound easy. It's not, but, but, you know, I think if, I think there's a real decent chance we could see a starship vehicle land on Mars, uncrewed by the end of the decade, though.

• 4:23:37Lex Fridman?

  End of the decade. I mean, there's also a sociological element, maybe a political one, where I think you're allowed to take more risks with Mars than you are with the moon. Because we've done the moon, 1969.

• 4:23:49Speaker 01

  Yeah.

• 4:23:50Lex Fridman?

  It's been a while, so PR wise, you have to be much safer.

• 4:23:54Speaker 01

  Yeah.

• 4:23:55Lex Fridman?

  With Mars, like everyone's like, it's super dangerous, like super, like, so you could take a little more risk.

• 4:24:02Speaker 01

  Hundred percent.

• 4:24:02Lex Fridman?

  Especially with the, with man missions. But actually, just going back to the moon landing, Apollo 11 mission. We haven't talked about this, Adam. The amazing engine there, but again, the romantic question, when you look back at that moon landing.

• 4:24:21Lex Fridman?

  One small step for man, one giant step for mankind. What do you think about that moment in human history? Do you go back to that often? Or are you focused just like with the cars on the, on the engines?

• 4:24:33Speaker 01

  No, no, I, I still, when I need inspiration, I rewatch this documentary called, When We Left Earth. I think it was like a, I think it was Discovery Channel did it. Six part episode. It, it was narrated by Gary Sinise. Phenomenal overview of the space race. And that will get my juices flowing every time, every time. Just, it's so well done and it's, it really just summarizes that program so well. And when I, and beyond, it goes all the way to the space shuttle, but. Yeah, when I, when I watch footage of humans walking on the moon, it's just, I can't believe we're dumb enough to do it with the technology we had and the risks they took

• 4:25:15Speaker 01

  to do it. And the insane engineering that it took to do that is just absolutely astonishing. The, the amount of the sheer like logistics of what it took to do it with the, the technology we had back then is like, how did we have so much money and effort and energy and time and resources, human resources to do this? Like, it's just.

• 4:25:40Lex Fridman?

  Just the weakness of the computers they had back then. They had to do so much. I mean, yeah, it's so much with so little.

• 4:25:47Speaker 01

  It's insane. And, but at the same time, like, I don't know if we want to talk about conspiracy theories or anything, but like, it is all of, like, we have the proof in the pudding of like, the 400,000 people on payroll, like, all of the paperwork, all of the.

• 4:26:02Lex Fridman?

  Oh, you mean the, the question of conspiracy, if we land on the moon?

• 4:26:05Speaker 01

  Yeah, like.

• 4:26:06Lex Fridman?

  Well, I mean, I, I think.

• 4:26:07Speaker 01

  The receipts are there, like, literally.

• 4:26:09Lex Fridman?

  We did. But it's like, a lot of things like that. I mean, we actually generally live in a, in a pretty cynical time where people distrust institutions. Part of the thing was the space program is one of the things that can help reinvigorate the trust in institutions. By institutions, even that word is a bad word now. But institutions means a bunch of humans get together and do a big thing together.

• 4:26:34Speaker 01

  Yeah.

• 4:26:36Lex Fridman?

  Yeah, but, you know, like, if I was conspiratorially minded, it's like, how the hell did humans do that?

• 4:26:45Speaker 01

  Yeah.

• 4:26:46Lex Fridman?

  So I, I think that's a very cynical take, unfortunately, but it's still an incredible one. And also, you know, there is, there's, until you look at the receipts, there's a kind of.

• 4:27:01Lex Fridman?

  Like a rationale to that kind of conspiracy theory because so much pressure was put on the space race, the PR of it to be the winner. So it makes sense that you might want to try to take shortcuts and fake things and, you know, propaganda, you know, different kinds of messaging. And I'm sure stuff like that was happening. Some kind of like little, you know, adjustment here and there to present things better and so on. But ultimately, the actual engineering project of landing on the moon, the fact that humans did that. I mean, it is sad that we didn't have better like ways to record it. And as I watch like SpaceX efforts and Blue Origin and these efforts, it's still not trivial to record

• 4:27:45Lex Fridman?

  the how just amazing awe inspiring spaces. Cause it like, you know, it's like Elon jokes about like space does look fake.

• 4:27:56Speaker 01

  Yeah.

• 4:27:57Lex Fridman?

  Like, I think there is some element of it where you have to be there to experience it really. And I don't like, I think it's currently is still an unsolved problem of how do you capture the awe of that? I mean, you're one of the early people that are part of the crew that is exploring that very question. I'm sure you won't find all the answers, but you will start to say like, how do we convert this into a visual format into some kind of format that captures the magic of it?

• 4:28:26Speaker 01

  Hundred percent. And that's a perspective thing that I think about all the time. You know, and I, I'll, I'll do a lot of thinking about like, what is the thing that's reacting to people? Is it the sound? Is it the perspective? Is it like seeing a little tiny human next to a landing leg that makes people go, oh my God, this thing is huge. You know, just reading, you know, and digesting that and trying to help to convey that as best as possible because the stuff that we are and have worked on is, is so cool. It's so exciting. And it's so, it's so important. And like actually, you know, So much bigger than any one of us physically and metaphorically. It's just so, it's just, I wish everyone had that, that experience and had that light bulb go off.

• 4:29:09Lex Fridman?

  And that's the cool thing that you're like smack in the middle of solving that really difficult and fascinating problem of how, how do you capture the magic? How do you inspire? Like, that's not just an engineer problem. That's a communication problem, education.

• 4:29:25Speaker 01

  I, I find specifically for myself that I get most excited about something when I learn a lot about it. Like when I learn the ins and the outs and I learn all the little problem solving and the, you know, the cool like, oh my God, they had to do what to make it work? Wow, that's amazing. And that's, I try to just always go back to that root thing of like, what can I teach myself? Like if I'm, every video, I, I expect that I learned something making it, no matter what. Like no matter how much I think I know about something, at the end of the day, if I'm not learning something, it's not a good video, you know? And I always think that people get excited when they learn and when they have some questions answered for them.

• 4:30:04Lex Fridman?

  Let me ask you a couple of quick out there futuristic questions I have to. I'd hate myself if I don't ask you. So first, let's talk about nuclear propulsion. So out there, interesting propulsion ideas. So what do you think beyond the chemical engines that we talked about? What do you think about using nuclear fission and maybe even nuclear fusion for, for propulsion?

• 4:30:30Speaker 01

  We already have thermal nuclear reactors. There are nuclear engines that have been tested both by the United States and Soviet Union that were a hundred percent valid, like totally ready to go. Efficient, super awesome. Yes, yes, yes. Hardcore, yes. And what, what they're using is, yeah, basically a fusion reactor. You're flowing hydrogen through it and heating up the hydrogen, taking it from liquid to a gas, you know? And by heating it up, you're, you're adding energy to the propellant. And then you're literally just using that now steam hot hydrogen and flowing it through a diol valve nozzle. And you also have to use that, that energy to spin the pumps to still pump the thing.

• 4:31:10Speaker 01

  So you're still kind of using like a lot of the tricks that you're using, but instead of a chemical reaction, you're literally just using. Nuclear fission to heat up propellant and do the same thing. And at the end of the day, you end up with like eight to 900 seconds of specific impulse, which is double that of chemical propulsion. Most of that comes just because hydrogen is so light. You're only emitting, you're only ejecting hydrogen out of the nozzle. So the lighter molecule is the faster, you know, just like if you had a, you know, it's a golf ball versus like a bowling ball. You can only physically throw one so fast. And the other one, as a human, you're not going to do very well with. So you can just, you get, you have the more potential for a higher exit velocity. So nuclear thermal, amazing.

• 4:31:55Speaker 01

  You can just shoot these little hydrogen molecules out crazy fast, crazy efficiently. We already have it. We can do it. Yes, yes, yes. And actually, we're already reinvesting in that again as the United States is, is looking into basically ramping back up our nuclear propulsion.

• 4:32:10Lex Fridman?

  Why haven't we done it yet? And what do you think the challenges are there? And do you think that's an obvious future? Like, would you, would you see in 50 years, we're not using, like, we're not, for major projects, like a starship type of project, we're not using chemical propulsion anymore?

• 4:32:28Speaker 01

  For getting off Earth, you'll always want to use chemical propulsion because the, the gas will come irradiated, like you don't, you don't want to. And, and actually, the thrust to weight ratio of these engines are relatively poor. They're, they're very heavy. They have a nuclear reactor, like they're not, they're really, the reason we kind of gave up on them is they're really most useful for like interplanetary. If you're trying to get a big, like, if you're trying to send a huge payload off to Mars, nuclear thermal is amazing. It's still could be beneficial even going to the moon. You know, like in an Earth, moon system, you could use nuclear thermal very effectively. It could be a great choice. But it also, that starts to get into that trade of like, eh, we can just kind of use a little bit bigger rocket and. And fly a normal, you know, it's that whole trade thing.

• 4:33:13Speaker 01

  But another reason why we kind of stopped using them, the one that the United States developed, NERVA, was so heavy, only a Saturn V could actually lift the stage of it, like the upper stage. So it replaced the S4B with a nuclear thermal with the NERVA engine. The Soviet Union developed one about one tenth the size and thrust that was small enough to fly on a proton rocket. But neither of them ever flew. Both of them have been tested and like thumbs up, ready to go, which is just a huge shame to me because they could unlock a lot of interplanetary potential and just all around

• 4:33:49Lex Fridman?

  awesome. Which potentially interstellar as well.

• 4:33:52Speaker 01

  Not, I don't think nuclear thermal, not, we're not quite getting there, but then you get into like nuclear pulse drives and things where you're literally like basically ejecting a bomb out the back of your rocket and exploding and having like a shock absorber and pogo sticking your way out of the solar system. That, that's, I mean, by all physics, sure, you know, there's not, nothing wrong with that. It's not breaking any laws of physics and, you know, I, but I just don't see us getting to that need anytime soon. I don't think we're gonna be.

• 4:34:21Lex Fridman?

  Interstellar travel.

• 4:34:21Speaker 01

  Yeah. I mean, that's, that's, I think we're going to want a better understanding of physics and.

• 4:34:26Lex Fridman?

  Physics itself. Yeah. Do you have a hope that maybe theoretical physics will open the door to some exciting propulsion systems?

• 4:34:34Speaker 01

  Yeah, I do. I think we're still at the very infancy of our understanding of everything and how things work. And, you know, a hundred years ago, it would be stupid to try to predict the things we know today. And who knows, like even, you know, I think about things like James Webb, looking deeper into our solar system than ever before and physically being able to see objects that we just have not even been able to physically see before.

• 4:34:56Lex Fridman?

  On being able to study black holes, for example, a better, better, the stuff that's happening outside of black holes, at the edges of black holes, how the information is stored, the holographic principles, just there's so much weirdness around black holes.

• 4:35:12Speaker 01

  Yes.

• 4:35:12Lex Fridman?

  Around where gravity starts bending light.

• 4:35:18Lex Fridman?

  It's like, all right, we'll get to look at that now and start to wonder like, what is going on? And how can we like use that somehow for propulsion? I mean, it seems like awfully crazy and futuristic at this moment, but I think that's because we know almost nothing about,

• 4:35:37Lex Fridman?

  you know, that those kinds of objects where again, where the general relativity and quantum mechanics start to, start to have to be both considered to describe those kinds of objects. And as we study those objects, we might figure out some kind of unification thing that will allow us to understand maybe how to use black holes to for propulsion like,

• 4:36:00Speaker 01

  Yeah.

• 4:36:02Lex Fridman?

  I could say a lot of crazy things, but like basically.

• 4:36:04Speaker 01

  But the, the point is it'd be stupid for us to even guess about things we don't even know about yet. You know what I mean? Like, and so therefore I'm not going to say that the best option for interstellar travel is nuclear drives like that could be like someone saying, you know, in 1600, the only way to fly is by strapping a thousand birds to your head, you know, like.

• 4:36:24Lex Fridman?

  But that said, I mean, everything you're saying is right, but the human history is such like at the beginning of the 20th century, physicists, Rutherford, they, everybody, there's, there's brilliant people that said, we've basically solved all of it.

• 4:36:38Speaker 01

  Right.

• 4:36:38Lex Fridman?

  If you talk to most physicists, I think they're going to say like, we've pretty much solved like the standard model describes physics extremely accurately.

• 4:36:48Speaker 01

  Right.

• 4:36:49Lex Fridman?

  General relativity explains the cosmos as we observe them extremely accurately. Yeah, there's a whole dark matter, dark energy thing, whatever.

• 4:36:57Speaker 01

  Yeah.

• 4:36:58Lex Fridman?

  But outside of that, we've, so like we've basically solved like,

• 4:37:04Lex Fridman?

  like where are you going to find gaps in knowledge that are going to somehow create warp drives or something like that? So wormholes. But that's, it seems like throughout history, we prove ourselves wrong time and time again.

• 4:37:19Speaker 01

  Yes. No, and I, this is well outside of any of my knowledge base. So I want to make sure that if I say anything stupid, it's because I'm just a peasant here in physics land.

• 4:37:29Lex Fridman?

  But yes, we're all peasants in physics land.

• 4:37:33Speaker 01

  But I really just think like, it's very humbling that we're still using chemical propulsion and variance of like injecting mass to propel ourselves. And I, no matter how you get at it, and I think someday, I would expect that our species has figured out a way to get beyond that.

• 4:37:51Lex Fridman?

  Got to ask you another wild question. What do you think of Bob Lazar, who claimed that he worked at and saw in Area 51, a propulsion system fueled by, I'm quoting here, maybe from Wikipedia, I don't know where I got this from, fueled by an antimatter reactor, which used as fuel the chemical element with atomic number 115. At the time, it wasn't synthesized. It was later in 2003 synthesized, named muscovium. He said that the propulsion system relied on a stable isotope of element 115, which allegedly generates a gravity

• 4:38:33Lex Fridman?

  wave that allowed the vehicle to fly and to evade visual detection by bending light around it. No stable isotopes of muscovium have yet been synthesized. All have proven extremely radioactive, decaying in a few hundred milliseconds. One, do you believe him? Which I find him fascinating because it's, I find the human mind even more fascinating than, than, than something like an antimatter drive. Because I think it's such a giant mystery that we haven't even begun to explore deeply. Anyway, in that sense, whether he's lying or not are both interesting things to explore from a psychology perspective.

• 4:39:17Lex Fridman?

  But two, he's basically saying that I guess it's an alien.

• 4:39:23Lex Fridman?

  Extraterrestrial engine thing.

• 4:39:30Lex Fridman?

  What do you think?

• 4:39:31Speaker 01

  I mean, I'm happy to change my opinion based on new evidence at any point. I have like, the biggest part of me wants to just be like, this is obviously just stupid and a hoax and just total, you know, quack.

• 4:39:46Speaker 01

  And then another part of me still is like, this is exciting and fun to think that this is all real. And then another part of me goes, why? How, how good is this guy at lying and making stuff up? Cause it's all really good, like good storytelling, good like, I don't know what to think, honestly. I don't know. I'm really very skeptical about anyone explaining anything like this. Like, I mean, my, my radar is like screaming at me like, this is all at full crap, you know? But I'd say like, there's still a part of me that's just like, man, that is kind of cool. How does he know that? And like, you know what I mean? It's, I'm conflicted.

• 4:40:23Lex Fridman?

  I think you're actually in the, in the best kind of place. Cause it's, um, I'm afraid of being the kind of person that hears something like that and says, is definitely, he's definitely full of crap and basically closed my mind off to all that stuff. I'm afraid of being somebody who closes my mind off to a thing that's actually a, a early thread to a brilliant, to a, to a future, to a fascinating solution to a mystery. So, uh, but in this case, I mean, I have so many red flags from a psychological perspective that, um, that I, but again, uh, outside of this particular individual, I do wonder if aliens have visited us. I think aliens are everywhere.

• 4:41:07Lex Fridman?

  I think the universe is teeming with alien life. And there's, it's very difficult for me to statistically understand, given how.

• 4:41:20Lex Fridman?

  Life finds a way here on Earth, just everywhere. The entire history of life on Earth, from the very origin of life, it seems to be damn good at doing its thing, evolving to get better and better and better at doing its thing. Now, there could be some special aspects to the origin of life itself, which is completely not understood. So maybe the true magic is in the origin of life. Or it could be that there is some magical leaps to your karyatic cells, for example, that the universe, our galaxies, teeming with alien life, but it's all bacteria. They're all boring bacteria or exciting bacteria. No offense to bacteria. But the no-intelligence spacefaring civilizations. I don't know.

• 4:42:03Lex Fridman?

  But I just, if I were to guess, if I had to bet all my money, there is spacefaring civilizations everywhere in the universe. And the fact that they're not, that they have not been directly, definitively observed, confuses me. And I think it's a mystery. And if I were to suggest what the solution to that mystery is, is they might look extremely different from us. And we might be too dumb to detect them.

• 4:42:33Speaker 01

  Yeah.

• 4:42:34Lex Fridman?

  And so there, I think you have to be extremely open-minded at what would we be looking for?

• 4:42:41Speaker 01

  Right.

• 4:42:42Lex Fridman?

  That, and that's a very practical thing to be open-minded about. And practically speaking, if we were to be able to even detect them from a distance, get a techno-signature of a distant planet, of a distant star system that has alien life. Honestly, the number one thing I kind of want to know is like, what's your propulsion system? Like, how do we travel faster, right? Like, there's a bunch of details, probably. But first, let's get together.

• 4:43:15Speaker 01

  And teach me how to go fast.

• 4:43:17Lex Fridman?

  Go fast.

• 4:43:17Speaker 01

  I like motorcycles, I like rockets.

• 4:43:19Lex Fridman?

  Exactly.

• 4:43:19Speaker 01

  Yeah, yeah.

• 4:43:20Lex Fridman?

  Uh, yeah, like how, like, I'll show you mine if you show me yours, kind of thing, at the interstellar, intergalactic level. Yeah, anyway, I just wonder, maybe it's a cheat code in this video game we call Life. But I want to, I want to use the cheat code to figure out what kind of propulsion systems are possible. And it feels like other alien civilizations might help us, give us...

• 4:43:48Lex Fridman?

  Give us a guidance on that. Of course, I think even just discovering, boy, one of the things with the space program, like everything we're doing with Mars, like the secret thing I'm really excited about, the romantic thing is humans on Mars, but the secret thing is building giant stations on Mars that allow us to definitively, hopefully find the traces of life that either currently doesn't live or has once lived on Mars. Because if that's the case, that means for sure life is everywhere.

• 4:44:23Speaker 01

  Oh, 100%.

• 4:44:24Lex Fridman?

  And then you're like, and once you know that, sorry to keep interrupting, not shutting the hell up. This is supposed to be an interview, god damn it. All right, that, like, that, just the knowledge of that, just the knowledge that a four-minute mile can be run, I think will open our minds completely to really, really hardcore push to interstellar travel or colonizing Mars, becoming multi-planet and zero species. It'd be truly inspiring.

• 4:44:51Speaker 01

  You think that?

• 4:44:54Speaker 01

  Do you, do you get nervous though? Like, I'm gonna, I'm the interviewer now. Don't you get nervous that we could make spectacular discovery on Mars that not only has there been life, there's actually like pretty advanced micro, you know, or multi-cellular life, totally thriving in certain regions we just hadn't visited in the manner of Mars, and we make this big discovery that a relatively large percentage of people just simply wouldn't believe it. They'd think it's all 100% fake and that they're just doing this to control us and that blah, blah, blah. Like, we could make the most important discovery in human life, like in all of human existence, that, that we're not alone in this universe, by, you know, cellularly at least.

• 4:45:39Speaker 01

  And a good percentage of people, I'm thinking 20, 30, in today's world, 40-plus percent of people wouldn't even believe it existed.

• 4:45:49Lex Fridman?

  Interesting. I, I'd be, it's just a very important thing to think about, especially as an educator like yourself. I think the the current cynicism towards institutions and science is temporary. I think it's they're basically the internet woke up. The internet smells bullshit and it looked at. I'm sorry, I'm not being ageist, but saying older scientists and they looked at them and they kind of said, you're kind of full of shit. You got a lot of ego. You're you speak down to everybody. You're not very good at communicating. I think there's a lot of truth to what they're saying. And I think the young scientists that are coming up will be much better at not being full of shit,

• 4:46:29Lex Fridman?

  being authentic, being real, not treating people like they're children that can't possibly understand, like taking it very seriously, that there's a lot of intelligent people out there that are curious, that are this full of desire for knowledge, like being transparent about all the uncertainties of the scientific process, all the tensions, the conflicts, all of that. And I I think I think once we fix the science communication system, adapted to the internet, I think that won't be an issue. I hope, I hope. I mean, that's why people like you are really important is is like communicate with authenticity.

• 4:47:10Lex Fridman?

  But yeah, that's definitely something to think about. I mean, yes, the early. I mean, listen, scientists too, like the phosphine discovered on Venus is like they're extremely skeptical always. So definitely there will there will be a lot of skepticism. And it depends what it looks like. If it kind of looks like this thing kind of looks like bacteria back on Earth. Yes. So it means contamination is very difficult to avoid in general. But if the thing looks like fundamentally different.

• 4:47:39Speaker 01

  Yeah.

• 4:47:40Lex Fridman?

  Then you're like, all right.

• 4:47:42Speaker 01

  Yeah.

• 4:47:42Lex Fridman?

  That like.

• 4:47:43Speaker 01

  Totally different DNA RNA. Like this is not, we've never observed this ever.

• 4:47:48Lex Fridman?

  Yeah, then then you're like, all right, cool. Of course, so that another promising thing that difficult to be definitive about, but let's get better and better direct imaging systems. There's now, I don't know how many, but thousands of planets are being discovered outside of our solar system. There's moons being discovered, now earth-like planets being discovered. So like all of that, if we could do direct imaging of those planets more and more and more, there could be some gigantic, listen, if there is like a car chef, like type two civilization, we're gonna see the damn thing. It's gonna be producing a lot of, it's gonna be radiating a lot of energy.

• 4:48:32Lex Fridman?

  So the possibility of detecting some of that, that's also a real possibility with something like James Webb telescopes, like those kinds of efforts that starts becoming a reality.

• 4:48:42Speaker 01

  Have you read Andy Weir's Project Hail Mary?

• 4:48:44Lex Fridman?

  I have not, no.

• 4:48:46Speaker 01

  You're going to love it. Like it is basically, almost answering that like, how could they not see us type of thing almost where he creates this incredible, I don't want to spoil anything, but you know, it's just the sense that like, we could have totally different perspectives with, with an alien race and not even like, consider that, you know, the two of us are coexisting almost.

• 4:49:12Lex Fridman?

  Yeah.

• 4:49:12Speaker 01

  I don't want to spoil anything, it's really, really, really worth the read.

• 4:49:15Lex Fridman?

  Oh, you mean a different perspective, like the aliens have a different perspective than humans?

• 4:49:19Speaker 01

  Yeah, like we just like, we see with this visual light.

• 4:49:23Lex Fridman?

  Yeah.

• 4:49:23Speaker 01

  Someone could see in x-ray, et cetera, you know, like, and just the way we even come to the same perspective and like, looking and observing is just so different fundamentally that like, we could, I mean, it's not quite like that. It's not like, it's like, oh, they were actually on the moon and we're, you know, it's not like that, but, but it's such a unique and incredible story. I think Andy Weir is one of the best science fiction writers. I don't, I can't say that with much authority because I don't listen to much science fiction. So zero authority. I really like Andy Weir's books and that book is no different.

• 4:49:55Lex Fridman?

  Well, that sounds like, I'm really worried about that. It sounds like, I would really love it. I've differently, I've been very.

• 4:50:04Lex Fridman?

  I've I've done a lot of reading in my life, but like the science fiction is one of the things I've been really, really weak on. I haven't really read much and I just made more and more friends over the years recently that say that I absolutely must read some of these things.

• 4:50:18Speaker 01

  Are you, do you physically read or do you do audiobooks while you run and stuff?

• 4:50:22Lex Fridman?

  Both. I do both. Yeah. But physically, I sadly don't. It's a Kindle, right?

• 4:50:27Speaker 01

  Yeah, yeah, yeah.

• 4:50:28Lex Fridman?

  Yeah. But, uh, but when I, while I run, I also do, uh, so I do both. I do about, uh, on a normal day, especially now that I've been really focused on, on reading. It's about 60 minutes of reading on a Kindle and one to two hours, uh, cause I run about two hours when I don't have like other stuff. Like today I won't run. Uh, so it's about three hours. So on average, I would say it's like two, two and a half hours a day that I read. And audiobooks are just the same. They're a little slower, but they're, they can, especially for the classics, they can capture some of the magic with a deep voice, usually with a British accent. I love it. I also read that, uh, listened to, sorry,

• 4:51:11Lex Fridman?

  that, uh, a book on propulsion like two years ago, I remember. But I remember that was extremely difficult.

• 4:51:18Speaker 01

  Ignition by?

• 4:51:19Lex Fridman?

  Yeah, it was ignition.

• 4:51:20Speaker 01

  By Don D. Clark?

• 4:51:21Lex Fridman?

  Yep. It was very difficult to listen.

• 4:51:23Speaker 01

  Oh, I, yeah, I see. I don't read. I, I listen while I'm on road trips or running or stuff like that, too. So I swear there's probably 40 or like not 40, but there's like eight minutes of, we tried BMZ 15, 13, BM412, RMNL, micromechal hydrogen for like, I swear it's multiple minutes of explaining one trial on something. Cause there's just so many different chemicals they try. I don't know. It's, it's, it's almost a joke. Like I literally audibly laughed out loud listening to it. Cause I'm like, this is so ridiculous. I'm sure it makes sense reading it, but like listening to it is just hilarious. But it's great though.

• 4:51:58Lex Fridman?

  What do you think of some of the challenges for long-term space travel? Do you think about this kind of stuff, the biological stuff?

• 4:52:06Speaker 01

  Yeah.

• 4:52:06Lex Fridman?

  Um, do you, do you worry? Do you think about radiation on Mars? Uh, and out in space over periods of, uh, actually the effects on the human body. Forget even the radiation over periods of months and years?

• 4:52:20Speaker 01

  Yeah.

• 4:52:23Speaker 01

  I think realistically, we have a really good handle on what the effects are. And we actually have the solution to like everything. It's just whether or not we can like, you know, for instance, one of the, you know, low earth orbit, one of the biggest challenges eventually after your long-term space travel is bone density loss and not having gravity, you know, you actually have issues with a handful of things and artificial gravity is easy in terms of relatively easy as in terms of spaceflight, you know, you can, you can have two vehicles just tethered together and, you know, just spinning as given enough distance and a decent enough spin velocity. And you can, you can get one gene like relatively easy.

• 4:53:07Speaker 01

  We're talking again relatively easy, especially after talking about theoretical physics like this is, that's easy stuff. We haven't done that yet, but like there's, there's no reason why we can't produce artificial gravity. If we say that that's, you know, a big enough hurdle that we absolutely have to overcome this, okay, cool, we'll just spin up two vehicles that are going to Mars and people will have, but you know, that's the thing is Mars is only about, we'll say six months there, then you're hanging out on Mars, you have 38% of gravity and then six months ish back. People live on, you know, the International Space Station at six month stints. We've had people for basically a year up on the International Space Station. It's not like it's, it's not life altering. Yeah, you have a couple of days of not being able to walk very well and you do have some

• 4:53:52Speaker 01

  bone density loss and some other concerns. But like, again, that's, it's solvable. And I think, you know, the first mission is to Mars. I think it might, we might, we'll probably do the trade. Is it worth it to like land on Mars and have a crippled crew that can't even physically stand yet, you know, for a day or two before they get their, you know, feet from underneath them? Or is it, do we need to spin up two spacecraft or, you know, a tether and have like, you can't do it like Starship, you know, even though it's 30 feet wide or nine meters wide. If you spin it on that one axis, that's not enough space to get one G without your feet and your head being at two different velocities. So you get really sick, it'll, you'll always feel like you're falling. Your brain will tell you that you're falling constantly.

• 4:54:38Speaker 01

  But then again, okay, so this is, this is a whole thing is. You know, and I don't know if there's, we don't really have the data yet on like going from zero G, we know the effects of that. We know the effects of one G really well. That's our majority of our data set, but we don't really have much data on the long-term effects of, you know, one-sixth gravity, like on the moon or 38% gravity. Is it, is one-sixth gravity actually enough to counteract 95% of the effects of low gravity? Or is it 15, you know, is it one-sixth? Is it like a linear thing? Is 38% gravity totally, you know, 38% as bad as one or whatever, you know, is it a slight, like where is it down on the scale? So there's a chance that we don't need anywhere near one G of gravity

• 4:55:21Speaker 01

  to counteract the bulk majority of these problems. We could have point one G or whatever is the, you know, the right compromise of, of vehicle complexity and human biology and all of these other effects. Like we, this is absolutely a solvable thing. That is.

• 4:55:38Lex Fridman?

  And we figure some of this out through just experimentation.

• 4:55:42Speaker 01

  Hundred percent.

• 4:55:42Lex Fridman?

  Along the way.

• 4:55:43Speaker 01

  Yep.

• 4:55:43Lex Fridman?

  Uh, one of this is back to my dating life. I think one of the essential fundamental research questions I'm wondering about is, uh, the dynamics and, um, so the details of how you have sex in space. Um, asking for a friend, of course. I mean, that's, there literally is sort of work on this, right? Cause like, if you think about long-term space travel, I mean, sex is, uh, so like the, there's the recreational aspect of sex, but the most important aspect of sex for long-term space travel is, um, uh, procreation is, and also the full biological cycle of that. So the, from the embryo to the development

• 4:56:26Lex Fridman?

  of the baby, the giving the birth and all that kind of stuff. So like, you know, there's a lot of really difficult.

• 4:56:34Lex Fridman?

  Problems of biology there to understand and perhaps solve some of that again, just like you said brilliantly, some of that can be just solved with engineering outside of the human body by creating a gravitational field like that, but maybe along the way you can figure out how to do that without doing it, but we're balancing the costs and so on.

• 4:56:53Speaker 01

  And radiation is the other thing. We know we have a really good data set on what radiation and doses do to humans. We know we can measure radiation. We know we can approximate, you know, and kind of give edge cases for the Mars transient and getting to Mars and being on Mars. And the simple answer to that is like, at the end of the day, if we have to, you know, dig into Mars or find a tunnel to live in, so you get some extra mass in between you and cosmic radiation, so be it. Like, that's the, that's the answer then. Again, none of these are like insolvable problems. They're just things, hurdles you would have to overcome based on, you know, the risk exposure and the posture there.

• 4:57:34Lex Fridman?

  Imagine being the first child, the first baby born outside of Earth. That'd be pretty cool. I would love to be alive to see that.

• 4:57:47Speaker 01

  That'd be a big one.

• 4:57:48Lex Fridman?

  I don't know if he'll, um, I don't know, because it's such a dangerous thing. It's so risky.

• 4:57:56Speaker 01

  I think that could be in our lifetime.

• 4:57:58Lex Fridman?

  You think so?

• 4:57:58Speaker 01

  Yeah. I, I would like to think in a perfect world of her thinking futurism that in 30 to 50 years, I definitely think we could have a full time, like, permanent major civilizations, you know, like, like, um, like what Blue Origin wants to develop, where they have a huge like sphere, you know, and you're doing a lot of, especially heavy industry off of Earth, so you're not polluting Earth. Like, that's makes so much sense to me. Um, yeah, I think, I think we.

• 4:58:29Speaker 01

  We could live in a lifetime where, you know, we thought that since the 50s and 60s that people are going to be living and working in space like crazy. And at any given point, we're lucky to have 12 people in space today. But I really think in our lifetime, we're finally getting to that point of, yeah, that that's a reality.

• 4:58:47Lex Fridman?

  Let me, because you mentioned Blue Origin, can we just lay out some of the competitors to SpaceX? So much of what we talked about is SpaceX specifically because they're sort of pushing the boundaries of what's possible in the commercial space light. But there's a lot of, like you said, incredible work being done for large companies and small companies, startups and so on. So who are the competitors to SpaceX? ULA, United Launch Alliance, Blue Origin, there's a Virgin, is it Galactic Orbit?

• 4:59:17Speaker 01

  Orbit would be the competitor.

• 4:59:19Lex Fridman?

  Virgin Orbit, there's Rocket Labs, Electron Rocket that you mentioned. There's the folks that you covered, Firefly?

• 4:59:28Speaker 01

  Yep.

• 4:59:29Lex Fridman?

  And what are we missing? There's the Epic Space Launch System from NASA, I guess that is?

• 4:59:36Speaker 01

  Technically NASA, but prime contractor Boeing and

• 4:59:39Lex Fridman?

  Boeing and Lockheed.

• 4:59:41Speaker 01

  Yeah, North was the boosters, yep.

• 4:59:43Lex Fridman?

  Nice. So like what's, what's interesting to say to lay out the land here that you're excited about?

• 4:59:48Speaker 01

  Just in general, I think if you aren't working on a reusable, some form of reusable vehicle, like physically working on it, pen to paper, or not beyond pen to paper, like bending metal for a reusable vehicle, you're gone, you're toast. I think we're well into that being the only provable, you know, way forward. The only way you're going to compete and survive is a reusable rocket. Fully reusable would be great, but that's obviously massively aspirational still. But it will come. But to me, The yeah, the list, you pretty much had it right on the head. There's, there's Astra was another orbital rocket company. They, there, there's a lot of companies. And I think right now,

• 5:00:31Speaker 01

  the, the ones that I personally really believe in, you know, Rocket Lab is, is awesome. I really think that they are one of the few that I believe can actually build a Falcon nine class rocket, like today with the, with their technology, with their knowledge, with their investments, with their funding, you know, they've, and they've proven themselves. There's very few, they have actually made it look easy. I think there's a lot of startups and a lot of new rocket. There's a too many launch providers popping out of the woodwork right now. They won't all survive, of course. I think realistically, if you look at like airplanes, how many airplane, you know, there's a handful of airplane manufacturers. There's not hundreds and thousands of airplane manufacturers. I think it'll be a similar thing for spaceflight. I think we'll

• 5:01:15Speaker 01

  see, we'll see, you know, realistically, in the terms of jumbo jets and passengers, there's basically two, you know, there's Airbus and there's Boeing. So I, I think in the long run, there'll be two or three major players. I think there'll be, you know, 10 minor, like as far as launch providers, as far as the ones actually leaving Earth and getting into orbit, I just don't think there's a ton of room for individuality, really, you know?

• 5:01:45Lex Fridman?

  Yeah, I would love to see it like a really serious competitor to SpaceX in the way that SpaceX does things. I don't know if you'll like, it's quite what I, it's quite the right kind of competitor.

• 5:01:57Speaker 01

  Let me, let me say this, ULA has all of the potential, but just operationally, they're, you know, they're, you're Lockheed Martin and Boeing's like love child. Yeah. But they're kind of set up in a far too traditional manner where they just really aren't given the opportunity to innovate like a lot of these startups are.

• 5:02:17Lex Fridman?

  So Rocket Lab is a little bit more of that nature. What do you think about sort of just Blue Origin in general?

• 5:02:23Speaker 01

  The origins, I, man, I What Blue Origin has done with New Shepard is amazing and people just laud it because it's suborbital and it looks very phallic.

• 5:02:35Lex Fridman?

  It's

• 5:02:37Lex Fridman?

  So I guess the meme matters also in this modern day.

• 5:02:40Speaker 01

  But it's sad because people don't see what they are also working on, which is New Glenn. You know, I see comments almost every day still of like, it doesn't matter because you know, they're, they're working on tiny. It's like, no, New Glenn is more powerful and more capable than Falcon Heavy. New Glenn is almost more of a competitor to, not quite as to Starship, but it's almost in that class. It's a, it's a heavy lift launch vehicle. It's huge. It's crazy. It'll be nuts. They're very actively working on it. You know, I still think we're three years away from it launching, but that's a very strong competitor in the class of rockets that SpaceX is currently making.

• 5:03:14Lex Fridman?

  So SpaceX is currently leading the way, but that, it couldn't become a close race.

• 5:03:20Speaker 01

  And what, it's just, I, we'll just, for now, we'll ignore SpaceX and we'll just kind of talk about like, I think who's kind of coming around the corner here, who's, so let me just do a quick overview. I'm, I'm going to shoot myself in the foot for getting some cool people here and some, some exciting companies. But Relativity is one that if you, you should definitely get Tim Ellis on the show, who is the CEO of Relativity. They're doing 3D printed rockets, the ones that have the world's largest 3D printer. They're getting really close to their first orbital launch. The cool thing about them, the reason that I think they're exciting, the reason that I, I think they have the potential is just how quickly they can iterate. I think 3D printing a rocket is really dumb. I think iterating with 3D printing on a rocket is brilliant because you can literally change software

• 5:04:05Speaker 01

  and have like very little, you know, upload a file and have a new rocket. Like, that's amazing. So in terms of long-term iterative process, if, if we're really talking about like hitting the ground running and, and just seeing where the, the evolution takes you, I think that's about as good as you can get. You know, I think what SpaceX is doing at Starbase, just physically bending cheap steel is probably also a very valid solution. So I really think, and they have the engineering chops. I think they've got some amazing people there. Again, Rocket Lab, I adore what they work on and you know, like everyone, there's a caveat here that everything takes longer. Anything, any company tells you it's two or three times longer, just period. Rocket Lab's no different, but I really, they're, they're working on a neutron rocket that's going to be

• 5:04:51Speaker 01

  like, I think 8,000 to 15,000 kilograms to lower throw, but like it's a good medium class rocket will compete right along with Falcon 9, hopefully.

• 5:04:59Lex Fridman?

  By the way, neutron will be its name.

• 5:05:01Speaker 01

  Yep, yep.

• 5:05:02Lex Fridman?

  It's not like kind of neutron. It's not some kind of fascinating new physics breakthrough where they're using neutrons.

• 5:05:06Speaker 01

  No, no, but they are using, they're also using liquid methane and liquid oxygen. I just think it's a really, it's a, seems like a great rocket and assuming they can actually get it flying in two or three years, I think they're going to be, it's here to stay, you know? I'd be remiss, right now I'm editing a video from an interview with Stoke Aerospace out in, in Kent, Washington. It was just one of these companies that they have a long ways to go. Like they're still in the very, they're, they're behind the curve frankly, in, in terms of launch vehicles right now, because like I said, there's so many coming out of the woodwork. But the idea they're working on, their solution to a fully reusable rocket is amazing. One of the coolest concepts I've ever seen.

• 5:05:48Lex Fridman?

  Are you going to cover it in the video?

• 5:05:49Speaker 01

  Yeah, yeah, yeah. That'll be hopefully coming out the next, depending on what the schedule like is down there. I'm, I'm working, I'm actively editing that as we speak and it is so cool. I mean, it is like, it's, it's genius and if they can actually get it to work, I can see them merging. I can for sure see someone potentially like I perfectly, in a perfect world, they've merged with Rocket Lab. They, Stoke develops the upper stage and maybe even the engines. They are, the two guys, the, the CEO, the co-founders of that company have, they are engine, like propulsion engineer magnificence. They have, they used to, they both have worked at Blue. They developed engines in a hurry there and then left Blue and it felt like it was getting too slow for them. And now they are,

• 5:06:31Speaker 01

  I mean, these, these guys fired a 15 chambered rocket engine instead of four from the Soviet and we're talking 15 chambers, single turbo pump, 70 times in the month of October. Wow, that's impressive. And that's like, that was on, you know, if you think about like days off, time off, you know, parts changing.

• 5:06:51Lex Fridman?

  Yes.

• 5:06:52Speaker 01

  Over twice a day on average of a hydrolox engine? That's insane. So I, I love them and I hope the best for them. But they're also topical right now. They're at the top of my head. So.

• 5:07:04Lex Fridman?

  What about Firefly?

• 5:07:06Speaker 01

  What I like about Firefly, they've already got kind of a traditional aerospace backing. They're starting to buddy up a lot with Northrop Grumman. So they're going to be building the booster stage for Antares, which is currently flying only out of Wallops, Virginia, and is one of the only other commercial providers for the International Space Station. And Northrop Grumman is a very traditional aerospace company, you know, like lots of solid rocket boosters and they've purchased ironically their, their current Antares is reliant on Russian engines and Ukrainian boosters, two things that I don't think you're going to be able to get your hands on too much anymore. So.

• 5:07:38Lex Fridman?

  Yes.

• 5:07:39Speaker 01

  They're looking to some US propulsion and stages. So they actually are partnering with, with Firefly and their new Antares rocket will be a first stage built entirely by Firefly. So I'm, I'm excited that Firefly already has the propulsion technology. And they actually developed ironically their, their tap off cycle engine was developed in partnership with Ukraine, with Ukrainian engineers who developed the, the whole turbopump system. So it's like, it's this cool meld, meddling of, of these worlds. Their former CEO, Tom Mercusick was, like I have an interview with him and he's, anyone that can just spout nuances and facts, I just love. I just soaked that guy's information

• 5:08:24Speaker 01

  up as best I could because he is brilliant, literally a doctor, a rocket doctor, you know, it's so.

• 5:08:30Lex Fridman?

  Yeah. I mean, that's what like you said, the fascinating thing about these folks, they're, they're legit. They're, they're such great engineers that people that, that bring these rockets to life. And then there's all this stuff that we know and don't know about in, in China and other parts and other nations that are putting stuff into orbit. One of the sad things also is like, you know, with Lockheed and Boeing is.

• 5:08:53Lex Fridman?

  And just military applications in general, there's so much technology that's currently being developed that we probably know nothing about.

• 5:09:00Speaker 01

  Yeah.

• 5:09:01Lex Fridman?

  And that makes me a little bit sad, of course.

• 5:09:05Speaker 01

  Yeah.

• 5:09:06Lex Fridman?

  For several reasons. One is that the use of that technology is has really much like it's not it's not that inspiring. It's like a very military focused.

• 5:09:16Speaker 01

  Yes, to kill someone.

• 5:09:17Lex Fridman?

  It's to kill someone. Yeah. There's not even like a side application.

• 5:09:23Speaker 01

  Right.

• 5:09:23Lex Fridman?

  And and the the big one is that the secret it's it's shrouded in secrecy as opposed to being a source of inspiration.

• 5:09:30Speaker 01

  Yeah, 100%.

• 5:09:30Lex Fridman?

  But that's the way of the world. Like, what was that one plane that you covered that was like, we know nothing about?

• 5:09:37Speaker 01

  Oh, the X 37B.

• 5:09:38Lex Fridman?

  Yeah, X 37B.

• 5:09:39Speaker 01

  Yeah, orbited for over 900 days and returned. Like, yeah, I want to know.

• 5:09:43Lex Fridman?

  What's that thing up to?

• 5:09:44Speaker 01

  I don't know. That's what's it's so frustrating. We know when it launches, people, you know, amateurs track and know they even will be like, oh, it changed orbit, you know, it raised and lowered its orbit, blah, blah, blah. We generally have just almost no idea what it's doing up there. And it just saddens me because I want to know. And it's awesome. It's a great vehicle.

• 5:10:05Lex Fridman?

  War. What is it good for? You mentioned Kerbal Space Program, the video game. Someone asked you what video game you recommend for learning about space and rockets, and you said, duh, Kerbal Space Program. So tell me about this game. What is this game? And I also saw heard that a second one is coming out. So what what?

• 5:10:29Lex Fridman?

  Like, you know, I've been playing more games recently because games are fun and they remind you that life is awesome. So why should I play this game?

• 5:10:40Speaker 01

  If you want to learn about rockets, how to fly, how to build, how to get into orbit, how to get to other planets, there's no better way to learn about rockets than playing Kerbal Space Program.

• 5:10:50Lex Fridman?

  What does it entail? Like, do you actually like?

• 5:10:53Speaker 01

  It's like SimCity and Microsoft Flight Simulator for rockets.

• 5:10:57Lex Fridman?

  Oh, interesting. So you will get to like, what do you design the rockets?

• 5:11:01Speaker 01

  Yeah. Yeah, it's okay. So I started playing it in like 2014, I think, around as I'm like falling in love with space and I became obsessed with this game like literally you, you know, you, you, you take a like you get boop, a little command module, click you click on a fuel tank, boop, you choose your engine, boop, you choose a stage connector, boop, you connect more tanks and build these space planes and fantastical things and it's all like physics based. It's available. This sounds like a commercial. It's available on PC, Mac and console. Like it's, it's available everywhere.

• 5:11:34Lex Fridman?

  But wait, there's more.

• 5:11:35Speaker 01

  But wait, there's more and.

• 5:11:37Lex Fridman?

  You, you, you said like you streamed yourself playing this. Are those any of those videos up?

• 5:11:41Speaker 01

  Oh, yeah. Yeah, there's some of my, actually, the first videos I ever uploaded to YouTube were re like recaptured streams from Twitch that are just physically uploaded to YouTube.

• 5:11:51Lex Fridman?

  This is awesome.

• 5:11:52Speaker 01

  And so it's, it's me playing Kerbal. We, I used to do this kind of like a podcast style thing. I should get back into this because it's one of my favorite things I ever did. It's called, we called it Todayish in Space Fight History, but these days I'd probably just play Kerbal. But I had my friend come sit next to me. His name's Jacob and he is a former professional pole vaulter, just this really knows nothing about rockets.

• 5:12:14Lex Fridman?

  Yes.

• 5:12:14Speaker 01

  Knows nothing about space hilarious, like in the sweetest, most fun way he like he, you know, as an adult asked me which is bigger, the earth or the moon? And I love that for him. You know, that's, that's fantastic. He's just a delightful human. He would sit next to me. We would recreate a historical spaceflight mission and Kerbal Space Program and he would just sit there and play guitar and sing about what I'm like doing and asking questions.

• 5:12:36Lex Fridman?

  Yeah.

• 5:12:36Speaker 01

  And it's still one of my favorite things I've ever done.

• 5:12:38Lex Fridman?

  Yeah, you should definitely do something like that. So basically just, uh, yeah, shoot the shit with a friend.

• 5:12:44Speaker 01

  Get their curiosity going. Let them just sit there and ask questions. It was awesome. Like, I mean, yeah, those are some, I, I've done it a handful of times. I think we probably did like 20 or 30 episodes or something and is, it's definitely something I would like to get back to doing.

• 5:12:58Lex Fridman?

  Can you in the, in the game like go to, go to the moon?

• 5:13:01Speaker 01

  Yeah. So it's technically a different solar system. It's the Kerbal system and you're on the planet Kerbin. So there's the Mun, M U N. There's a second moon in the system on this planet. It's called Minmus.

• 5:13:15Lex Fridman?

  They didn't want to pay licensing fees or what?

• 5:13:19Speaker 01

  Well, it's just a little easier. It's a little bit smaller. So the physics are easier.

• 5:13:23Lex Fridman?

  Oh, so it tries to be consistent with physics?

• 5:13:25Speaker 01

  Yeah. Oh, yeah. The physics are all are all like real world physics. And I mean, there's aerosimulations. There's all of it's like one to one, you know, for Earth physics.

• 5:13:34Lex Fridman?

  Awesome.

• 5:13:35Speaker 01

  It's just on an easier scale solar system. So it's easier to navigate, but there's still like, there's a planet called Eve. That's kind of like Venus. So it has a really thick atmosphere, really thick, really soupy. It's it's and a lot more gravity. So it's just really, really hard to get off of. It's easy, relatively easy to land on Eve, but like, that's kind of like the ultimate boss in the game is like getting off of Eve. So that's one of my favorite things to do is build these crafts to get to Eve and try to return home.

• 5:14:02Lex Fridman?

  You mentioned that there's almost like a podcast thing. You also did our ludicrous future. What is there a podcast in your future? Are you are you thinking? Do you enjoy the medium? You're so incredibly good at talking. It's less effort to

• 5:14:19Lex Fridman?

  sort of to produce. Are you? Is that something in the in the back of your mind also?

• 5:14:23Speaker 01

  Oh, man, I love talking.

• 5:14:27Lex Fridman?

  Yeah, you're very good at it. I mean, yeah.

• 5:14:30Speaker 01

  I I find that I it's just the problem with for me with with podcasts, and I think that's the podcasts that I've done have tried to be relatively topical about like the current spaceflight affairs. And for three or four years ago, that was actually, you know, manageable for me to keep up with. These days, man, I can't keep. I just can't keep up with it. I gave up on trying to be super topical and I realized that maybe my my biggest talent and the things that resonate most with people is just trying to explain the like, the basics and the and the root really get. So I'm really just trying to like,

• 5:15:09Speaker 01

  I'm trying to do less live streams if I can. But then again, like Starship, I gotta stream that. There's no way I'm not going to do that. But I'm really just trying to get back to like making the deep dive videos where I have no limit on how long and how deep and just really go for it because that's actually what I love to do the best.

• 5:15:25Lex Fridman?

  Yeah, I mean, that's like views aside, those are just works of genius and you're getting better and better at them. And like, that's the

• 5:15:34Lex Fridman?

  That in terms of the beautiful things you can create in this world, those are that. So like if you continue, especially where the way space travel is developing.

• 5:15:43Speaker 01

  Right.

• 5:15:43Lex Fridman?

  Like that, your voice is very much needed. So I think it's wise to um to do what you do best.

• 5:15:51Speaker 01

  And I think I'm feeling more and more, especially this last year, I did a lot of like live streaming and traveling back and forth between Florida and California and here and just handling major like big live streams. Really stress myself out. And at the end of the day, I was like, all of this is taking away from my ability to make videos. And that's ideally, honestly, if I like had my choice of things, I would just ignore everything else and just sit and lock myself in a in in my house for a year and just sit there and make videos and go and travel every every other month, you know, for fun, like not for space stuff. Just go and do some light traveling, you know, some.

• 5:16:28Lex Fridman?

  Like around the moon or what?

• 5:16:30Speaker 01

  Yeah, just some light traveling.

• 5:16:34Lex Fridman?

  What advice would you give to young folks or just folks struggling to find their way in life, whether they're in high school, college or beyond? Like how to have a life they can be proud of, how to have a career they can be proud of. You've had a really interesting journey yourself. What from that can you draw?

• 5:16:53Speaker 01

  Man.

• 5:16:54Lex Fridman?

  Give advice to others.

• 5:16:56Speaker 01

  To be honest, like I feel like it's so painfully obvious to follow your heart and follow like what makes you happy that I'm just shocked that people allow themselves to sit on like mediocrity, you know, like to just sit there and be like, well, this is just what I do, you know, and something for a lot of people, that's perfectly fine. Like I have, you know, some of my best friends are clocking in and out and they're perfectly happy. They have a wonderful life, absolutely no judgment there, of course.

• 5:17:21Speaker 01

  But for people that are stuck, feeling like they're not sure of, you know, what's next and how to bring light into their world. You really just gotta listen to like, what does make you happy? You know, people feel guilty about, oh, I play video games for eight hours. Then start learning how to make a video game, learn how to do reviews of video games or make, there's so many, you can work in the video game industry, you know, you don't have to isolate your love from your work, you know, and it's just funny that we, you know, maybe. Uh, maybe you feel guilty that you drink too much. Okay. I don't know if this is a good advice. Go, go learn how to make alcohol, you know, be a-

• 5:17:58Lex Fridman?

  Start a liquor company.

• 5:17:59Speaker 01

  Yeah, start a liquor company.

• 5:18:01Lex Fridman?

  No, it's a great, it's great advice, but it's also in your own story. It seems like you've almost stumbled on like, some of it is just exploration and keeping your mind and heart open to discovering that thing that grabs you. Right?

• 5:18:15Speaker 01

  What do you fall asleep thinking about? You know, like-

• 5:18:18Lex Fridman?

  But you, you stumbled on the space almost accidentally, right? I mean-

• 5:18:22Speaker 01

  Yeah, yeah.

• 5:18:23Lex Fridman?

  I could, would you, when you were doing a, being a professional photographer, would you have known?

• 5:18:28Speaker 01

  Oh, no. Well, do you want to know what I wanted to be when I was a kid?

• 5:18:31Lex Fridman?

  What's that?

• 5:18:32Speaker 01

  Well, first, when I was young, I wanted to be a tractor. I'm not quite sure I understood.

• 5:18:35Lex Fridman?

  Yeah.

• 5:18:36Speaker 01

  How that works. Then I wanted to be a scorpion trainer.

• 5:18:39Lex Fridman?

  Yeah.

• 5:18:39Speaker 01

  Thought I could train him to cut people's lawns.

• 5:18:41Lex Fridman?

  Better and better.

• 5:18:42Speaker 01

  Yep, yep. And then honestly, the majority of my childhood-

• 5:18:45Lex Fridman?

  People's lawns, God. I think your understanding of physics early on was just a little-

• 5:18:50Speaker 01

  The pinchers, man, pinchers.

• 5:18:53Speaker 01

  Then, uh, from like probably six until like early college, I wanted to be a prosthetic engineer. And never once did I think about anything rockets, really. You know, I had like a, I had like a space shuttle poster. I had some space shuttle Legos. You know, I liked space and, you know, I knew of the space shuttle, but, uh, you know, it was a far down the list as far as things that I thought were cool. Ninja Turtles, Lamborghini Countach, B17G Flying Fortress.

• 5:19:24Lex Fridman?

  Yeah, I guess, I guess that means if you just keep your heart open to falling in love with an idea, with a passion, yeah. You could start from that, from Ninja Turtles and scorpions cutting lawn to, uh, being one of the best, one of the top educators, inspirational figures in space. And actually traveling around the moon. And who knows, maybe one day stepping foot on the moon and Mars, even though you say you're not interested, it seems like you stating that you're not interested in certain things somehow results in you, uh, in you doing those things.

• 5:19:59Speaker 01

  My friends joke that like, I'm going to be the first person to go to the moon against their will.

• 5:20:03Lex Fridman?

  Like, I guess, all right. This is, uh, all right, what's the food like up here?

• 5:20:07Speaker 01

  Guys, we're going to start a fundraiser. Please, like, Tim just doesn't want to have to, he doesn't want to go, you know?

• 5:20:12Lex Fridman?

  Definitely don't want to do it. All right, Tim, you're an incredible person. Thank you so much for everything you do. I've been a fan of yours for a long time, not just the content, but just who you are as a human being, just how excited you are for everything. It's just an inspiration. You're a joy to watch. Thank you for being you. Thank you for doing the stuff you're doing. I can't wait to see what you do next. And thank you so much for talking with me today. That was awesome.

• 5:20:36Speaker 01

  Thank you so much. It's my pleasure.

• 5:20:38Lex Fridman?

  Thanks for listening to this conversation with Tim Dodd. To support this podcast, please check out our sponsors in the description. And now, let me leave you with some words from H.G. Wells. "Life, forever dying to be born afresh, forever young and eager, will presently stand upon this earth as upon a footstool, and stretch out its realm amidst the stars." Thank you for listening and hope to see you next time.