Cosmic Queries – Planets and Stuff

Neil deGrasse Tyson and comic co-host Paul Mecurio are back together again to answer your fan-submitted questions on Saturn, Jupiter, neuroscience, tidal forces, lunar exploration, and the science behind your hat size, and more. NOTE: StarTalk+ Patrons and All-Access subscribers can watch or listen to this entire episode commercial-free here: https://www.startalkradio.net/show/cosmic-queries-planets-and-stuff/ Thanks to this week’s Patrons for supporting us: Kay Gilbert, Brendan Brown, Akasha Yi, Tom Hernke, Jonathan Gaffers Photo Credit: NASA, ESA, and A. Simon (NASA Goddard) [Public domain]

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

• 0:00Neil deGrasse Tyson?

  From the American Museum of Natural History in New York City, and beaming out across all of space and time, this is StarTalk, where science and pop culture collide. This is StarTalk, and I'm your host, Neil deGrasse Tyson, your personal astrophysicist, and today is Cosmic Queries, Planet Edition. But we don't just stick to planets. This one is planets and stuff.

• 0:30Neil deGrasse Tyson?

  And today, I've got Paul Mecurio with me. Paul?

• 0:33Paul Mecurio?

  How are you?

• 0:34Neil deGrasse Tyson?

  Welcome back!

• 0:35Paul Mecurio?

  Thank you.

• 0:35Neil deGrasse Tyson?

  You're damn near irregular.

• 0:37Paul Mecurio?

  I, please, that's all I want to do.

• 0:39Neil deGrasse Tyson?

  No, I didn't call you irregular, a-regular. Did I pronounce that? Did you hear?

• 0:43Paul Mecurio?

  No, but it's that, yeah, actually, I kinda am a little bit, but we can get into that later. I have a couple of questions about how I can fix that, but we'll deal with that later.

• 0:49Neil deGrasse Tyson?

  Fix the irregularities.

• 0:50Paul Mecurio?

  Exactly.

• 0:51Neil deGrasse Tyson?

  Uh, great to have you on this.

• 0:52Paul Mecurio?

  Yes, so glad to be back, thank you.

• 0:54Neil deGrasse Tyson?

  And our normal format is, we solicit inquiries from our fanbase on different platforms, and the questions come in, I haven't seen them yet.

• 1:01Paul Mecurio?

  Right.

• 1:01Neil deGrasse Tyson?

  This is not Stump Neil Day, but it's, if I don't know the answer, I'll say, "Next one, please."

• 1:07Paul Mecurio?

  I've never seen you have to say "next one."

• 1:09Neil deGrasse Tyson?

  No, usually I have something to say about it, even if I don't fully know the answer.

• 1:12Paul Mecurio?

  You're right, exactly.

• 1:14Neil deGrasse Tyson?

  But just to tell people, I, did we first meet on, at Stephen Colbert?

• 1:18Paul Mecurio?

  We first met at the Stephen Colbert--

• 1:19Neil deGrasse Tyson?

  Because you're the warm-up guy.

• 1:20Paul Mecurio?

  Yeah, I, warm-up on that show, I was a writer on The Daily Show.

• 1:23Neil deGrasse Tyson?

  Oh, that goes even further back, yeah.

• 1:25Paul Mecurio?

  So, yeah, and then The Colbert Report, and I just came to say, I was a big fan once, you were very nice, and then I came back, the next time I asked for a loan, you said, "No, Mr. Big Shot doesn't have any extra money," okay? And then you, and then you were nice enough to come on my podcast, which has still gotten, like, one of the top listens, just, it's--

• 1:44Neil deGrasse Tyson?

  Really, excellent, excellent.

• 1:45Paul Mecurio?

  Yeah, we talked about dark matter and all this other stuff, and, uh, and then you asked me for money for that, and I'm like, "That's inappropriate, I don't have any money, you have them?" No. So, yeah, so we go back.

• 1:55Neil deGrasse Tyson?

  Yeah, yeah, so it's great, it's great to have you and see--

• 1:57Paul Mecurio?

  Yeah, thank you.

• 1:57Neil deGrasse Tyson?

  And we are, uh, reporting now from YouTube, New York City, in the Google building--

• 2:02Paul Mecurio?

  Yes, this is such a cool space.

• 2:03Neil deGrasse Tyson?

  And YouTube production space, and so, uh, they're kind enough to-- So, I, I miss all my books behind me, maybe I can have, like, a plastic version of it, just slide it in.

• 2:11Paul Mecurio?

  You could, you could have them photoshopped in later. And it's right above the Chelsea Market, I got, like, a ham sandwich in my parking lot.

• 2:18Neil deGrasse Tyson?

  Oh, yeah, yeah, you can't walk through without buying food.

• 2:19Paul Mecurio?

  I know, exactly.

• 2:20Neil deGrasse Tyson?

  Yeah, I don't know why any skinny people exist in this building, that's not possible.

• 2:23Paul Mecurio?

  There's actually a Weight Watchers office here, it's pretty weird. But, yeah, it's great to be here, and it's really cool space, I didn't know this was here.

• 2:30Neil deGrasse Tyson?

  Yeah, yeah.

• 2:31Paul Mecurio?

  And I always say, and I'm gonna say it again, if I had you as a science teacher, I'd be doing science today.

• 2:34Neil deGrasse Tyson?

  Really, seriously?

• 2:35Paul Mecurio?

  I say that, I don't, I don't--

• 2:37Neil deGrasse Tyson?

  Wow.

• 2:37Paul Mecurio?

  Right, Carol, I don't, yeah, that's my wife. And, uh, because you make it accessible, your personality, you clear, it comes, it brims, it brims with sort of, you love it, and you explain it in a way that's interesting.

• 2:50Neil deGrasse Tyson?

  You know what Carl Sagan said? He said, "When you're in love, you have to tell the world."

• 2:52Paul Mecurio?

  Right. I had a eighth-grade math teacher, this Bill, big hulky guy, he smoked in the class, and he was like, and we made a battery, like, that was the big thing, like--

• 3:02Neil deGrasse Tyson?

  Okay.

• 3:02Paul Mecurio?

  Right? "No, you put the thing over there," it was like this, like-- It's like, he was like, one step away from going off-track betting, you know? And, and I just remember being intimidated by him, and I, and I, and I think people are very intuitive from a young age, and can sense if somebody cares or doesn't care.

• 3:18Neil deGrasse Tyson?

  Oh, yeah.

• 3:18Paul Mecurio?

  And he did not, and that's why I think--

• 3:20Neil deGrasse Tyson?

  Oh, come on, thank you.

• 3:21Paul Mecurio?

  Yeah.

• 3:21Neil deGrasse Tyson?

  And just--

• 3:22Paul Mecurio?

  Look at me, I love you, man.

• 3:23Neil deGrasse Tyson?

  I love you, man! It's not your fault, it's not your fault!

• 3:28Paul Mecurio?

  It's me, it's me!

• 3:31Neil deGrasse Tyson?

  The, um, just a little bit back at you, um, I deeply respect your profession. The people who take information in the world, shape, reshape it, hand it back to you in a fresh perspective, and make you laugh at it.

• 3:45Paul Mecurio?

  Well, thanks.

• 3:46Neil deGrasse Tyson?

  These, these are very special mirrors, and I don't know how bearable society would be without them, without the comedian who occasionally shows up and said, "You realize this is what you've been saying?" And, "Oh, my gosh, oh, haha!" And--

• 3:59Paul Mecurio?

  Right.

• 3:59Neil deGrasse Tyson?

  So, uh, this is why comedy is a fundamental part of what we do on StarTalk.

• 4:03Paul Mecurio?

  Yeah, well, it's, thank you, I mean, you know, when I started on The Daily Show, we were just this little show, and, you know, we were just doing jokes--

• 4:09Neil deGrasse Tyson?

  Right.

• 4:09Paul Mecurio?

  And didn't really say, "Okay, we're gonna have an impact on the world," or whatever, right? And then, things started to happen, and we were always factually based in our--

• 4:18Neil deGrasse Tyson?

  In the comedic, yes, sure, sure.

• 4:19Paul Mecurio?

  Right? And so, you have to start with the premise. So, we were delivering the news with a non-biased point of view, and just saying, "This, this seem a little strange to you?"

• 4:28Neil deGrasse Tyson?

  Mm-hmm.

• 4:28Paul Mecurio?

  So, over time, people come up to us and go, "I only get my news from The Daily Show." I go, "Well, first of all, we're a bunch of idiots, I don't think you should do that." Read some papers.

• 4:37Neil deGrasse Tyson?

  So, you say, "What the hell's wrong with you?"

• 4:38Paul Mecurio?

  Yeah, exactly. Read a couple of newspapers. But, uh, it did end up becoming that, and then, you know, from that, the, uh, The Colbert Report, The Late Show, John Oliver Show, Sam Bee Show--

• 4:49Neil deGrasse Tyson?

  Yeah, the whole, the whole universe.

• 4:50Paul Mecurio?

  Yes, it's all sort of carrying that mantle of, "Let's call people, you know, to the carpet." And so, yeah, so, thanks, yeah, we, we, it was a nice byproduct of trying to have some fun.

• 5:02Neil deGrasse Tyson?

  Yeah.

• 5:02Paul Mecurio?

  And we get in so much trouble, too, because we would go too far with jokes--

• 5:05Neil deGrasse Tyson?

  Yeah, yeah.

• 5:06Paul Mecurio?

  And the President Network would yell at us, but anyway, we'll talk about that another time.

• 5:09Neil deGrasse Tyson?

  So, what do you got for me? You got planet questions?

• 5:11Paul Mecurio?

  I got some planet questions.

• 5:12Neil deGrasse Tyson?

  All right.

• 5:12Paul Mecurio?

  Some very good ones and interesting ones, and questions and answers I want to hear. So, let's start with Patreon--

• 5:18Neil deGrasse Tyson?

  Oh, yeah, I keep forgetting we do this.

• 5:20Paul Mecurio?

  Yes, he says--

• 5:21Neil deGrasse Tyson?

  We're just kissing up to the Patreon members.

• 5:23Paul Mecurio?

  Yes, exactly, "Ryan, you are so handsome." "That shirt you're wearing looks fantastic on you." Write a check. "Is it true that if one had an ocean large enough, Saturn would float?"

• 5:36Neil deGrasse Tyson?

  So, this is often said, I've said it, colleagues of mine have said it, let me restate that in a more scientifically precise way.

• 5:48Paul Mecurio?

  Okay.

• 5:49Neil deGrasse Tyson?

  All right? Because technically, that can't happen, all right? You can't get a bathtub--

• 5:54Paul Mecurio?

  It would be one hell of a bathtub.

• 5:56Neil deGrasse Tyson?

  It would be a hell of a bathtub, I'll tell you why that couldn't happen in a minute. So, the scientifically precise way to communicate that same information is that the average density of Saturn is less than the density of water. And anything that, whose density is less than water, will float. So Saturn, so the technical way to say it is, if you scoop out a piece of Saturn, it will float on a, on, on, on a puddle of water, or in an ocean, it doesn't matter. So, that's the way to say it. It's more fun to say, "Get an ocean or bathtub big enough, Saturn will float."

• 6:30Paul Mecurio?

  Right.

• 6:30Neil deGrasse Tyson?

  And I've said that publicly, lamenting that when I was a kid, I knew this was true about Saturn, and all I ever had in the bathtub was a rubber ducky, and I really wanted a rubber Saturn. Because it was fun. So, so, later in my life, we come back to my office, someone mailed me a rubber Saturn.

• 6:48Paul Mecurio?

  Is that right?

• 6:49Neil deGrasse Tyson?

  Yes, I now have a rubber Saturn. And I can't, I don't, I wanna leave it in my office, I don't want to take it home to my bathtub, but, um--

• 6:56Paul Mecurio?

  "Honey, what's a rock doing in the bathtub?" It's a long story.

• 7:00Neil deGrasse Tyson?

  So, I've got a rubber Saturn. So, the problem is, if you had a lake bigger than Saturn, to put Saturn in, the whole lake would collapse into Saturn.

• 7:10Paul Mecurio?

  Well, wouldn't the water just spill over onto the shore? When you put, when it displaced the water?

• 7:15Neil deGrasse Tyson?

  No, no, no, you're thinking that they exist independently of each other. Saturn will pull the bathtub into it, and it'll become part of Saturn.

• 7:25Paul Mecurio?

  Oh, it's got the suction power.

• 7:27Neil deGrasse Tyson?

  Unless, well, yeah, it's called gravity.

• 7:32Paul Mecurio?

  Okay, you didn't need--

• 7:33Neil deGrasse Tyson?

  It's an old joke!

• 7:34Paul Mecurio?

  It's a little condescending, you didn't need to say it like that.

• 7:36Neil deGrasse Tyson?

  It's an old joke!

• 7:39Neil deGrasse Tyson?

  There's no such thing as gravity, Earth sucks. See, that's, that's, that's the old joke.

• 7:42Paul Mecurio?

  Nice. That's funny.

• 7:46Neil deGrasse Tyson?

  So, so, uh, so what was it, what was I, where was I? Oh, so, the problem is, you can't have a body of water bigger than Saturn that's flat, that you're gonna put Saturn in. Because the body of water would become a sphere, and they collapse, they fall into each other, all right? They each have mutual gravity that they'll attract each other. So, it's not a doable experiment--

• 8:06Paul Mecurio?

  Right.

• 8:07Neil deGrasse Tyson?

  But it does get the point across--

• 8:08Paul Mecurio?

  Yes.

• 8:08Neil deGrasse Tyson?

  That Saturn is lighter than water.

• 8:10Paul Mecurio?

  Plus Saturn would need a life jacket, in case something happened.

• 8:12Neil deGrasse Tyson?

  No, that's what the ring is for.

• 8:14Paul Mecurio?

  Oh, come on!

• 8:16Neil deGrasse Tyson?

  Got you on that one! That's his little life preserver!

• 8:20Paul Mecurio?

  I'm getting out of comedy now.

• 8:23Paul Mecurio?

  That's great, okay.

• 8:23Neil deGrasse Tyson?

  Yeah, so, so, it is in fact true, it is the only planet for which that is true. Every other planet would sink.

• 8:29Paul Mecurio?

  And it would absorb all the water.

• 8:31Neil deGrasse Tyson?

  And by the way, Jupiter is very gaseous, and it's, its density is close to that of water, but just a little bit above it.

• 8:37Paul Mecurio?

  Now, how do we know this about Saturn? I mean, how--

• 8:40Neil deGrasse Tyson?

  Oh, yeah, so what you do, that's great, good, do we go there, and, no, so you know how big it is? So, what is density? It's how much mass you have in the volume that you occupy. So, it's literally mass divided by volume.

• 8:52Paul Mecurio?

  Okay.

• 8:53Neil deGrasse Tyson?

  Grams per cubic centimeter. Pounds per cubic inch, that's density. Those are the, the units of density. So, we know the size of Saturn, and we know the mass of Saturn, we can measure it from its gravity and other things. You divide those two numbers, you get a number that's less than one.

• 9:11Paul Mecurio?

  And that means?

• 9:12Neil deGrasse Tyson?

  In the right units, and the density of water is one. Yeah, by definition, basically. Yeah, yeah.

• 9:19Paul Mecurio?

  So, we know.

• 9:21Neil deGrasse Tyson?

  Yeah, it'll float.

• 9:22Paul Mecurio?

  Alright.

• 9:23Neil deGrasse Tyson?

  And, um, here's something I figured out about myself just a couple of weeks ago. I was swimming a couple of weeks ago, and I was floating more easily than ever I have in my life.

• 9:34Paul Mecurio?

  But you had a lot of hair, you needed a haircut?

• 9:36Neil deGrasse Tyson?

  No. No, I'm just a little chubbier than I was when I was younger, because fat floats and muscle sinks. That's the thing, it's about the density. How much mass are you packing into a volume?

• 9:47Paul Mecurio?

  So why do you think?

• 9:48Neil deGrasse Tyson?

  You can say, how much does a whale weigh? Well, a whale weighs nothing. It's, it's, it's neutrally buoyant, floating, swimming in the water. You have to ask, how much mass does it have? It's why the biggest animals that ever existed exist in the water. They don't have to hold up their own weight against the gravity on Earth's surface. The whale is the biggest creature that ever existed in the history of life on Earth.

• 10:19Paul Mecurio?

  And yet it can float?

• 10:21Neil deGrasse Tyson?

  Because its density is about the same as water. If you are less than water, it would have to use energy to stay underwater, because the water would want to make it float.

• 10:30Paul Mecurio?

  Which is happens to human beings.

• 10:32Neil deGrasse Tyson?

  Well, if you're real, if you're chubbier, you will, your body will float. Okay, will float very well. And you'll take energy to go down below. If you are more dense than water, you will sink to the bottom and it'll take energy to stay afloat. If you're about the same density as water, you can move through the water with no, you know, like the the ease of a trapeze, or whatever that line goes in the song. So, so, following up on that, here's something interesting, ready? You know who the smartest person in the world was? You raising your hand? No.

• 11:07Neil deGrasse Tyson?

  One of the most clever people in the world was the first person to figure out you can build a ship, and everything you make the ship out of is denser than water, and it can float. You can, you can build a ship out of steel and have it float.

• 11:25Paul Mecurio?

  That does blow me away when I see it.

• 11:27Neil deGrasse Tyson?

  This changed, it changed warfare.

• 11:32Paul Mecurio?

  And was it a specific scientific?

• 11:33Neil deGrasse Tyson?

  Pause, you gotta, can you pause on that sentence, please? It changed warfare. You don't have to build your boat out of wood.

• 11:42Paul Mecurio?

  Right.

• 11:42Neil deGrasse Tyson?

  Which is susceptible to cannonball fire.

• 11:46Paul Mecurio?

  Right.

• 11:46Neil deGrasse Tyson?

  You can build it out of steel.

• 11:48Paul Mecurio?

  Right.

• 11:49Neil deGrasse Tyson?

  How do you get it to float? Because the part of the boat that sits below water is mostly air. The hull of the ship sits below water. So, so what matters is not that steel is heavier than water and air is lighter than water, it's what is the average density of that which you have plunked in the water? It's the total volume divided by the total mass. It has less mass than you think, because most of it is air. An aircraft carrier, most of its volume is air.

• 12:23Paul Mecurio?

  So it's able to float because of the relation of density to the water?

• 12:27Neil deGrasse Tyson?

  Correct, correct. Anything that's floating has, is less dense than water on average, period.

• 12:33Paul Mecurio?

  And do you think that that was by mistake, a byproduct of something else, that somebody figured out steel can float?

• 12:39Neil deGrasse Tyson?

  No, they were making canoes out of wood, because wood floats, and why would you make it out of anything else?

• 12:43Paul Mecurio?

  But then the steel, the next step was steel?

• 12:46Neil deGrasse Tyson?

  In order for it to float, it has to have a significant amount of volume underwater, so that the air can represent this.

• 12:51Paul Mecurio?

  Right.

• 12:51Neil deGrasse Tyson?

  Okay, so?

• 12:53Paul Mecurio?

  So the larger the vessel, the deeper the hull for the most part?

• 12:57Neil deGrasse Tyson?

  Generally, it's not going to just be skimming, it's going to sink in.

• 13:00Paul Mecurio?

  Right.

• 13:01Neil deGrasse Tyson?

  It's going to respond to that, the fact that there is steel there.

• 13:04Paul Mecurio?

  Yeah.

• 13:04Neil deGrasse Tyson?

  And then it'll come down to the level that's just right.

• 13:07Paul Mecurio?

  Right.

• 13:07Neil deGrasse Tyson?

  For what the weight is. If you look at container ships, they have these lines painted on the side of the hull, depending on how much gross weight it's carrying. So the more weight it's carrying, okay, the heavier the thing is, the total density goes up, and it's going to sink a little lower into the water.

• 13:24Paul Mecurio?

  Got it.

• 13:25Neil deGrasse Tyson?

  Yeah.

• 13:25Paul Mecurio?

  And they, they know when that they reach their max capacity.

• 13:28Neil deGrasse Tyson?

  Yeah, so ice is denser than cork. So?

• 13:33Paul Mecurio?

  That's counterintuitive in looking at ice versus cork.

• 13:36Neil deGrasse Tyson?

  Well, cork is from a tree, so you know it would float, but it's less dense, because ice, evidence of that is, the cork will float almost entirely above the water.

• 13:45Paul Mecurio?

  Right.

• 13:45Neil deGrasse Tyson?

  There's hardly anything sunk below it.

• 13:47Paul Mecurio?

  That's true.

• 13:47Neil deGrasse Tyson?

  Whereas ice, ninety percent of it is below the water.

• 13:51Paul Mecurio?

  Which is why you have icebergs.

• 13:53Neil deGrasse Tyson?

  It's why you have the iceberg problem, yeah. And James Cameron in Titanic, he did it right, okay?

• 13:59Paul Mecurio?

  Did he?

• 13:59Neil deGrasse Tyson?

  When they hit, basically, when they hit the iceberg, it's this little thing in the water. It's just, it's a little thing.

• 14:05Paul Mecurio?

  Sticking out of the surface?

• 14:06Neil deGrasse Tyson?

  It's just a little thing sticking, ninety percent of it is underwater!

• 14:08Paul Mecurio?

  Right.

• 14:09Neil deGrasse Tyson?

  That's what cut up the side of the hull!

• 14:11Paul Mecurio?

  Right.

• 14:11Neil deGrasse Tyson?

  Oh my gosh, whereas in the first Titanic movie, the black and white, nineteen forties, whatever, there's this huge iceberg out there. Oh my gosh!

• 14:25Paul Mecurio?

  Then it has a hand that reaches out.

• 14:27Neil deGrasse Tyson?

  And cuts it.

• 14:28Paul Mecurio?

  It's got a knife.

• 14:29Neil deGrasse Tyson?

  It's in a knife fight.

• 14:30Paul Mecurio?

  It's like West Side Story on the ocean. Once a jet, oh, he's a jet.

• 14:37Neil deGrasse Tyson?

  So, so, if you do the physics right, you don't need a big iceberg, and in fact, this has contributed to why it was, one of the several reasons why it was so hard to notice. It was, it's actually small.

• 14:48Paul Mecurio?

  Dark, it was foggy?

• 14:50Neil deGrasse Tyson?

  Dark, there wasn't any moon. It wasn't foggy, but it was, yeah.

• 14:53Paul Mecurio?

  Somebody was watching YouTube on their phone. We're gonna move on, that's fantastic.

• 14:58Neil deGrasse Tyson?

  Oh, my favorite anachronistic quote is a quote from Abraham Lincoln, where he said, "Never trust anything you see on the internet."

• 15:09Neil deGrasse Tyson?

  It's a meme!

• 15:11Neil deGrasse Tyson?

  It's so beautiful, it's just, you just gotta, you gotta love it.

• 15:14Paul Mecurio?

  Yeah, you gotta love it, and coming from him, you know, he's got a lot of credibility on him.

• 15:18Neil deGrasse Tyson?

  Yeah, he does!

• 15:19Paul Mecurio?

  You know, I'll give it to you.

• 15:20Neil deGrasse Tyson?

  It's a man that knew what the hell he was talking about.

• 15:22Paul Mecurio?

  The stovepipe hat, eh, questionable choice there, but, not in a buckle on a hat.

• 15:27Neil deGrasse Tyson?

  Yeah.

• 15:27Paul Mecurio?

  What do the pilgrims need a buckle on a hat for?

• 15:30Neil deGrasse Tyson?

  He wasn't a pilgrim. Wait, wait, excuse me, this is two hundred years later. Would you get your time period straight?

• 15:33Paul Mecurio?

  I understand that.

• 15:34Neil deGrasse Tyson?

  It was a top hat without a buckle.

• 15:35Paul Mecurio?

  But this is where my brain goes this way. Answer that question, smarty pants! Why do you need a buckle on a hat? Somebody letting their head out?

• 15:42Neil deGrasse Tyson?

  Well, no, you can squeeze it down in case the wind blows. It tightens up on your, on your brim.

• 15:46Paul Mecurio?

  The wind and the density and the volume and the whale.

• 15:49Neil deGrasse Tyson?

  Oh, I taught you too much?

• 15:51Paul Mecurio?

  You created, the student has become the master. Alright, you're gonna eat that cookie later I gave you, right?

• 15:57Neil deGrasse Tyson?

  Wait, I got a quick one, since we're talking about hat brims. Do you know the size of your own hat that you wear?

• 16:03Paul Mecurio?

  I have a pea head, pea, like pea brain, pea head. I'm like seven and a half small, I have a small head.

• 16:08Neil deGrasse Tyson?

  Seven and a half would not be a small hat, that's a large hat, yeah.

• 16:11Paul Mecurio?

  Don't, don't argue with me about my head size.

• 16:13Neil deGrasse Tyson?

  So you got a fat head, if that's, if that's your actual head.

• 16:15Paul Mecurio?

  No, no, it's like?

• 16:15Neil deGrasse Tyson?

  No, no, no, no, no.

• 16:16Paul Mecurio?

  Six, and then it's probably six and a half.

• 16:18Neil deGrasse Tyson?

  Six, it could be, so here's?

• 16:19Paul Mecurio?

  Your head!

• 16:20Neil deGrasse Tyson?

  Here's, I have a fat head.

• 16:21Paul Mecurio?

  Yeah.

• 16:21Neil deGrasse Tyson?

  So here's the?

• 16:22Paul Mecurio?

  It's a building, that's really what it is, but anyway, go ahead.

• 16:25Neil deGrasse Tyson?

  So, so I don't know if you knew this, but that hat's size has mathematical significance.

• 16:31Paul Mecurio?

  Please tell me it's not in relation to my you-know-what.

• 16:34Neil deGrasse Tyson?

  No, it's not. Not that I know that you know what I know what you said you know what. So here's what you do, you take a tape measure and measure the circumference of your head.

• 16:43Paul Mecurio?

  Okay.

• 16:44Neil deGrasse Tyson?

  Write down that number, divide it by pi, that's your hat size.

• 16:50Paul Mecurio?

  Oh.

• 16:50Neil deGrasse Tyson?

  Yeah.

• 16:51Paul Mecurio?

  I just thought it was that.

• 16:53Neil deGrasse Tyson?

  No, no, no, no.

• 16:54Paul Mecurio?

  Oh, you gotta divide by?

• 16:55Neil deGrasse Tyson?

  If you're, if the circumference of your head is six and a half inches, you know, you're not, you're some other species.

• 17:01Neil deGrasse Tyson?

  You're a rhesus monkey, I don't know, but you're...

• 17:04Paul Mecurio?

  Well, my wife would agree with you about some other species. You don't want to see me with my clothes off, it's not pretty.

• 17:11Paul Mecurio?

  I'd say, okay, well, I just learned another thing, because I just thought what my head size was literally like you just measured.

• 17:16Neil deGrasse Tyson?

  No, no, no, no, no, no, you must have never really put those two numbers together. So, I was in a hat shop, because I always wanted to own a top hat that you can pop into.

• 17:24Paul Mecurio?

  Oh, yeah.

• 17:24Neil deGrasse Tyson?

  I always wanted to want, and they make hats, so I, they measured my fat head, and they wrote it down and said, we need, you need a size eight, or something. So I said, fine, do you know where you get this number? He said he didn't know, and I told him. He said, really, really? So we did it, and so, I'm glad that he was skeptical, so then you can do the experiment. We did it on his head, and it's his assistant's head, it all came out! It was all perfect! And so, he wanted me to write it out, so I wrote it out, and I signed it, and it's on the wall of his hat shop.

• 17:49Paul Mecurio?

  That's fantastic.

• 17:51Neil deGrasse Tyson?

  With the pi and the arithmetic.

• 17:53Paul Mecurio?

  Can you imagine him going home, and then, honey, how was work? Well, this dude came in and he did math problems all day, but I sold a four hundred dollar hat, so I guess it was a good day. That's so awesome, you signed it and it's on the wall?

• 18:04Neil deGrasse Tyson?

  It's on the, it's on the wall.

• 18:06Paul Mecurio?

  That's better than like a diner that gets you to sign a picture of yourself.

• 18:08Neil deGrasse Tyson?

  Yeah, yeah, no, why would I picture me? Why, no, you want to put something that can advance human understanding of the universe.

• 18:14Paul Mecurio?

  That came from your giant, ghoulish head.

• 18:19Neil deGrasse Tyson?

  Oh, now ghoulish is part of the adjective.

• 18:21Paul Mecurio?

  This is my last time doing the show, by the way.

• 18:23Neil deGrasse Tyson?

  Okay, we ran out of time to do a second question in this segment.

• 18:27Paul Mecurio?

  Oh, sorry.

• 18:27Neil deGrasse Tyson?

  So when we come back, we will continue with StarTalk, Cosmic Currys and Atlantis.

• 18:43Speaker 02

  Bringing space and science down to earth. You're listening to StarTalk.

• 18:58Neil deGrasse Tyson?

  We're back, Cosmic Queries, second segment of three. Paul Mecurio, always good to have you. What did you tweet at what?

• 19:06Paul Mecurio?

  At Paul Mecurio, one R in my last name, M-E-C-U-R-I-O, yeah.

• 19:10Neil deGrasse Tyson?

  Okay, so good. There were no other Paul Mercurios in the Twitterverse.

• 19:12Paul Mecurio?

  Well, I had to change the spelling of my name because, no joke, there's an Australian actor, Paul Mecurio, and he got in the Actors Union before I did.

• 19:21Neil deGrasse Tyson?

  Oh.

• 19:22Paul Mecurio?

  So you can't have the same name.

• 19:23Neil deGrasse Tyson?

  Still, that's still the case.

• 19:24Paul Mecurio?

  So I dropped the first R in my name.

• 19:26Neil deGrasse Tyson?

  So Mercurio.

• 19:26Paul Mecurio?

  Yeah.

• 19:27Neil deGrasse Tyson?

  Yeah.

• 19:27Paul Mecurio?

  And people still think I'm him sometimes. He's hosting a reality beer show in Australia.

• 19:32Neil deGrasse Tyson?

  That's a thing, okay.

• 19:33Paul Mecurio?

  And so, yeah, he makes like craft beer, and so like every couple of weeks.

• 19:36Neil deGrasse Tyson?

  Craft or crap?

• 19:37Paul Mecurio?

  No.

• 19:37Neil deGrasse Tyson?

  What, I missed the last syllable.

• 19:39Paul Mecurio?

  No, there's an F in there, craft.

• 19:40Neil deGrasse Tyson?

  Craft.

• 19:41Paul Mecurio?

  Yeah. And I get, every two weeks or so, I get beer recipes from people thinking I'm him.

• 19:46Neil deGrasse Tyson?

  Okay.

• 19:47Paul Mecurio?

  And I'm like, okay, is that me? So anyway, at Paul Mecurio.

• 19:50Neil deGrasse Tyson?

  All right.

• 19:51Paul Mecurio?

  That's my thing.

• 19:51Neil deGrasse Tyson?

  Let's go for it.

• 19:52Paul Mecurio?

  Robert Weaver, also Patreon.

• 19:54Neil deGrasse Tyson?

  Good.

• 19:55Paul Mecurio?

  Thanks very much for continuing to educate and inspire us. What news in science do you find the most interesting or important? Is it the private space race?

• 20:04Neil deGrasse Tyson?

  No, I know too much about the private space race for that to be uniquely interesting to me. Things that interest me are things I know little about, and so that I want to know more about. I love watching the progress of neuroscience. I think the brain, our inner universe, in its attempt to contemplate the outer universe, presents one of the greatest intellectual challenges of our modern times.

• 20:30Paul Mecurio?

  And what advancements are we making right now that either surprised you or?

• 20:36Neil deGrasse Tyson?

  My view of the field, which is a very unpopular view among psychologists, is that the day will come when, I'm hypothesizing this, that the day will come where we understand the neurosynaptic phenomena in the brain with such precision that no one will ever have to lay down on a couch and spend an hour with a psychologist.

• 20:58Paul Mecurio?

  Because I do that. And I, seriously, and like, there's a lot of stuff I gotta figure out and work out.

• 21:04Neil deGrasse Tyson?

  Right. And some of it, so maybe there's...

• 21:08Paul Mecurio?

  Let me tell you about my mother. So, no.

• 21:10Neil deGrasse Tyson?

  So, so there may be things where people just need someone to talk to. That's one thing. But if you have some trauma, or some issue that you can't shake, or some addiction you can't overcome, I'm imagining there's a day we'll find the exact spot of the brain that's responsible for it.

• 21:29Paul Mecurio?

  And what would be?

• 21:30Neil deGrasse Tyson?

  That prevents you from pushing that next glass of, of highball away from you.

• 21:35Paul Mecurio?

  Or to go into depression, or whatever it might be.

• 21:37Neil deGrasse Tyson?

  Oh, depression, especially depression, where, or anything else that lands you in one of these, one of these...

• 21:44Paul Mecurio?

  Funky states or whatever.

• 21:45Neil deGrasse Tyson?

  Or the, one of these hospitals, in these mental hospitals. So that's the spot that's misfiring.

• 21:51Paul Mecurio?

  Okay, but what are we doing to the spot? Are we going in and operating? Are we taking a medication or a certain...

• 21:55Neil deGrasse Tyson?

  At this point, who knows? Is it too much firing, or is it not firing enough? Where there's another, it has to be another path into it that connects to this other brain center that helps modulate it? I don't know.

• 22:05Paul Mecurio?

  Okay.

• 22:05Neil deGrasse Tyson?

  I'm imagining that a future will arrive where we have that much knowledge and control of what's going on in the brain, so that you can just nip and tuck and fix all of these problems.

• 22:17Paul Mecurio?

  And why wouldn't psychologists welcome this theory?

• 22:20Neil deGrasse Tyson?

  Because they'd all go out of business overnight. Because you don't go into anybody's office for an hour and talk to them, excuse me, not for an hour, for a whole suite of sessions that could go on for years, that gets resolved in an afternoon.

• 22:33Paul Mecurio?

  I think my psychologist is making up a lot of stuff. I think I'm fine. I really do. And I think that, what do you mean?

• 22:40Neil deGrasse Tyson?

  And it's not just the whole community. There's counselors and psychologists, psychiatrists, this sort of thing. We're kinda almost there. There's a lot of depression that is not cured, but addressed by medication. All right? We know what chemicals will leave you in a depressed state, which ones don't, and why. Is it the production of those chemicals? Well, let's go in, adjust your genome, or your neurosynaptic drivers in such a way that you're producing your own chemicals, so you don't need the pill.

• 23:09Paul Mecurio?

  Right, because the problem with some of these pills is there's this sort of whack-a-mole, you fix one problem, and then there's sort of, you know, byproduct symptoms or problems.

• 23:16Neil deGrasse Tyson?

  Correct, because the pill gets ingested and it goes into your whole system.

• 23:20Paul Mecurio?

  Right.

• 23:20Neil deGrasse Tyson?

  Whereas if you surgically go in to one part of the brain for one... So now, what, one of the challenges to that future is the brain is highly interconnected to itself.

• 23:29Paul Mecurio?

  Okay.

• 23:30Neil deGrasse Tyson?

  So, an inability expressed in one part of the brain, some of that is also in other parts of the brain, which is how you can compensate for some brain injuries.

• 23:41Paul Mecurio?

  It's not compartmentalized.

• 23:42Neil deGrasse Tyson?

  It's not as compartmentalized as we'd want it to be, for it to be a nice, clean thing.

• 23:46Paul Mecurio?

  Right, right, right, right.

• 23:47Neil deGrasse Tyson?

  Right, right. And while we're on the subject, did you see the movie, what's the one with Scarlett Johansson? And sure, she...

• 23:54Paul Mecurio?

  Oh, she's a...

• 23:55Neil deGrasse Tyson?

  And her brain powers increased throughout it.

• 23:57Paul Mecurio?

  Yeah, I can't remember the name.

• 23:58Neil deGrasse Tyson?

  Is it Lucy?

• 23:58Paul Mecurio?

  I think it's Lucy, yeah.

• 24:00Neil deGrasse Tyson?

  Lucy, yeah. So, the entire premise of that film is that she takes some drug, turns out by accident, but it boosts her brain power, not to something she didn't, or any of us don't already have, it just enabled her to access the 90% of the brain that you're not using, okay? Well, where did this whole premise come from? And by the way, there are whole scenes in this film of rooms full of psychologists studying her as a phenomenon. Okay. It comes from some guy 100 years ago or so, I forgot his name, forgive me, who, through brain injuries and other aspects of, because you can't just go and start poking around in someone's brain.

• 24:40Paul Mecurio?

  You can?

• 24:43Neil deGrasse Tyson?

  You sound like you have been.

• 24:44Paul Mecurio?

  Yeah.

• 24:44Neil deGrasse Tyson?

  I gotta stop that, cross that one off my list.

• 24:46Paul Mecurio?

  I got a guy in my basement.

• 24:47Neil deGrasse Tyson?

  You got a guy.

• 24:48Paul Mecurio?

  I gotta probably let him go now. All right.

• 24:50Neil deGrasse Tyson?

  Yeah. So, what he said was, what he published was, "The brain is so complex, we know only what 10% of it is used for."

• 25:01Paul Mecurio?

  But how is he...

• 25:02Neil deGrasse Tyson?

  Well, excuse me, that became, "We only use 10% of our brain."

• 25:08Paul Mecurio?

  But how do, how do we know he's right? It's a theory.

• 25:10Neil deGrasse Tyson?

  No, no, no, you're in, you're in the wrong room right now.

• 25:14Paul Mecurio?

  All right, I'll leave then.

• 25:15Neil deGrasse Tyson?

  No, what he's...

• 25:16Paul Mecurio?

  No, I'm done.

• 25:18Neil deGrasse Tyson?

  I can't work like this.

• 25:19Paul Mecurio?

  Yeah, there's a band, there's a band playing downstairs.

• 25:21Neil deGrasse Tyson?

  There is. The YouTube music space.

• 25:24Paul Mecurio?

  Exactly.

• 25:25Neil deGrasse Tyson?

  It doesn't matter whether or not he's accurate, and he probably was accurate. He said, "Well, there's a, there's a language center here, and there's another..." All he said was, "We only, the brain is so complex, we only know what 10, what 10% of it is used for." That's all he said. A completely innocent comment. "We have much more to learn about the brain." It got re-quoted as, "We only use 10% of our brain."

• 25:53Paul Mecurio?

  Oh.

• 25:54Neil deGrasse Tyson?

  This is my point.

• 25:55Paul Mecurio?

  That's how I know it.

• 25:56Neil deGrasse Tyson?

  You weren't paying attention to what I... Okay?

• 26:00Paul Mecurio?

  Sorry, teacher.

• 26:00Neil deGrasse Tyson?

  And if you think we use only 10% of your brain, this is the mantra for teachers with students.

• 26:08Paul Mecurio?

  Right.

• 26:09Neil deGrasse Tyson?

  It's a very hard thing to correct when saying it incorrectly is what you want to hear.

• 26:17Paul Mecurio?

  Why do you think we want to hear that?

• 26:19Neil deGrasse Tyson?

  Because we want to believe that we all have potential we can grow into. Okay? Here's the underachieving student, you're just using 10%, keep working on what, using more of your brain, you have vastly more potential.

• 26:32Paul Mecurio?

  Right.

• 26:33Neil deGrasse Tyson?

  We're into potentiality.

• 26:34Paul Mecurio?

  Right.

• 26:35Neil deGrasse Tyson?

  All right? Especially in America.

• 26:36Paul Mecurio?

  Okay. Now, I'm gonna teach you how to tie your shoe again when you're six, and seven years old, or whatever it is.

• 26:41Neil deGrasse Tyson?

  You've got potential, okay.

• 26:41Paul Mecurio?

  But you can do more.

• 26:42Neil deGrasse Tyson?

  So that then became the premise of this entire movie. She's now using 40% of her brain, she's now using 60%, and at 80%, she's like, flying through webpages, learning whole dictionaries in a matter of minutes, and she's even changing her hair color with her brain and starts doing telekinetically, which is weird, like, why should a smarter person be able to move things with their mind? That's not an obvious next step for being smarter.

• 27:07Paul Mecurio?

  Maybe the object feels intimidated by the brain power and just wants to get out of the room.

• 27:11Neil deGrasse Tyson?

  It just seems to me you solve problems faster. That's all. Smarter people don't have telekinetic powers.

• 27:16Paul Mecurio?

  Yeah.

• 27:16Neil deGrasse Tyson?

  Right?

• 27:17Paul Mecurio?

  That's really true.

• 27:18Neil deGrasse Tyson?

  Right. And all, all the movies did this.

• 27:20Paul Mecurio?

  I am so smart. Toaster, come to me!

• 27:24Neil deGrasse Tyson?

  There's no, that's not a thing!

• 27:28Paul Mecurio?

  I went, I was in Best Buy the other day, and there was a guy making TVs fly. It was crazy.

• 27:33Neil deGrasse Tyson?

  He was a really smart guy.

• 27:34Paul Mecurio?

  Right. So, but with all of our abilities, if...

• 27:37Neil deGrasse Tyson?

  So I'm intrigued by that branch of science. That's what started the question.

• 27:40Paul Mecurio?

  Fascinating. So 100 years ago, 100 years is a long time, why haven't we been able to get to know more than 10% of the vein, brain, 12%, 50%, 20%?

• 27:50Neil deGrasse Tyson?

  Two reasons. It's hard to study the thing that is giving you the thoughts to study the thing.

• 27:57Paul Mecurio?

  Oh.

• 27:57Neil deGrasse Tyson?

  It's very, it's very recursive, right?

• 28:00Paul Mecurio?

  You just blew my mind, man.

• 28:03Neil deGrasse Tyson?

  You want to hear another recursive? Recursion is, is very mind-blowing. You ready?

• 28:06Paul Mecurio?

  Yeah.

• 28:06Neil deGrasse Tyson?

  Because I recently got a word into the Oxford English Dictionary.

• 28:09Paul Mecurio?

  Did you really?

• 28:09Neil deGrasse Tyson?

  Did you know about that?

• 28:10Paul Mecurio?

  No!

• 28:10Neil deGrasse Tyson?

  Yeah, yeah, yeah. The Manhattan Henge was in there. It was first used by Neil Tyson in 2003. I said, "What took you so long? 16 years later, but I'll take it."

• 28:19Paul Mecurio?

  What's, wait, what's the word again?

• 28:20Neil deGrasse Tyson?

  Manhattan Henge. You know Manhattan Henge?

• 28:22Paul Mecurio?

  Oh.

• 28:22Neil deGrasse Tyson?

  Those are two days of the year where the sunset aligns on the Manhattan grid, and now thousands of people flood the streets blocking traffic. It's a great...

• 28:29Paul Mecurio?

  Oh my gosh.

• 28:30Neil deGrasse Tyson?

  Think about all the other reasons traffic had been blocked. You know, there's an accident, or construction, or Con Ed is digging, you know, New York's electric company, but now we stop it for the universe. I'm loving it. So anyway, so get a word, so here's, you ready? Every word in the Oxford English Dictionary used to define every word is also in the Oxford English Dictionary.

• 28:57Paul Mecurio?

  Okay, so if I look up a definition of something-

• 29:00Neil deGrasse Tyson?

  All the words they assemble to define that word are themselves- Each one of those is in the Oxford English Dictionary.

• 29:07Paul Mecurio?

  So it's not possible to have a word in there that is not in the dictionary but is indeed a word?

• 29:12Neil deGrasse Tyson?

  Because then, that's why it would be in the dictionary defined.

• 29:15Paul Mecurio?

  But how do we know that they have it covered?

• 29:19Neil deGrasse Tyson?

  We don't, but what we do know-

• 29:20Paul Mecurio?

  And I'm not even being funny there, you know what I mean? Like, you got a limited group of people-

• 29:23Neil deGrasse Tyson?

  We don't, but we know that they have it covered better than anyone else. It is their singular mission in life to record every use of every word-

• 29:35Paul Mecurio?

  Yeah, but you're biased. You got a word in there. You're gonna kiss their rear end all day. "Oh, you're so smart, the Oxford Dictionary people."

• 29:42Neil deGrasse Tyson?

  I didn't say they succeeded this, I'm saying this is their mission statement. To have every usage of every word, ever, in the English language. So if a word first appears, they have the first appearance of that word. If you use that word slightly differently, pivoting its definition, that usage is then given.

• 30:03Paul Mecurio?

  Oh, wow.

• 30:03Neil deGrasse Tyson?

  You pivot it again, it's given. There it is.

• 30:05Paul Mecurio?

  And this gets back to the point about the brain, because the brain can get only to 10% because the thoughts that you need, it's that-

• 30:12Neil deGrasse Tyson?

  No, no, forget the 10%. It was misinformation from the very beginning.

• 30:15Paul Mecurio?

  No, I understand that, but when I asked about, "Well, why can't with all this-"

• 30:18Neil deGrasse Tyson?

  Well, it's one of the challenges. How do you study the thing-

• 30:20Paul Mecurio?

  That's right.

• 30:21Neil deGrasse Tyson?

  That is the thing that's studying the thing?

• 30:23Paul Mecurio?

  Right.

• 30:24Neil deGrasse Tyson?

  A. B., you can't just sit there and operate on people for scientific experiments. You know, Paul, I want to know how you think. So can I remove your top part of your skull and put electrodes in your brain just for my science experiment?

• 30:38Paul Mecurio?

  How much would you give me? Would you take over my mortgage? I would very happily have you open up my skull, my tiny skull.

• 30:48Neil deGrasse Tyson?

  Size 6.5, we got it.

• 30:49Paul Mecurio?

  Yeah, exactly.

• 30:52Neil deGrasse Tyson?

  Another question.

• 30:53Paul Mecurio?

  There's a follow-up to this, which I think is worth it.

• 30:54Neil deGrasse Tyson?

  A follow-up, go.

• 30:55Paul Mecurio?

  Why doesn't the matter in Saturn's rings accumulate like the matter in a protoplanetary disk?

• 31:02Neil deGrasse Tyson?

  Ooh.

• 31:03Paul Mecurio?

  I know the answer to this, because it gets cleaned once a week by a guy with a shop vac. Anyway, go ahead.

• 31:08Neil deGrasse Tyson?

  No, that's not it. So the Saturn's rings are very thin, and they're small particles, and they're very thin. And the matter does collect. It collects into certain zones, clearing out other zones. So in fact, Saturn's rings have gaps in them.

• 31:25Paul Mecurio?

  Which you kind of see.

• 31:26Neil deGrasse Tyson?

  You can see with a medium-power backyard telescope. And in fact, it's not just simply a gap. You can see like the ball of Saturn through that gap when it's at the right angle. So you know there are no particles there, or at least very few. So they collect, not in a sphere, but they collect orbitally, alright? Because they have stable orbits around Saturn, and they're not much mass there to begin with, they're not gonna overcome this orbit and then coalesce into one moon, for example. When our moon was created, we had a ring. That whole ring collapsed into a moon, because of huge chunks of material that were there, whose gravity wins, and it's winner takes all.

• 32:07Neil deGrasse Tyson?

  If you have slightly more gravity than this other object, you will attract slightly more material than this will.

• 32:13Paul Mecurio?

  And those larger objects in what was the ring around the moon came from just sort of meteor-

• 32:19Neil deGrasse Tyson?

  Earth had a collision. We were side-swiped by another planet.

• 32:22Paul Mecurio?

  Right.

• 32:23Neil deGrasse Tyson?

  And our Earth's crust got spewed into orbit around us, into a ring, and that ring then coalesced into the moon. And so, there you have it. So, one of the most depressing things I learned, because I'm not an orbital dynamicist, so I'm reading some papers from some colleagues, was to learn that Saturn's ring system might just be temporary.

• 32:45Paul Mecurio?

  Why?

• 32:45Neil deGrasse Tyson?

  Well, because they track the orbits, and the orbits are not stable. You're losing them down into Saturn itself.

• 32:52Paul Mecurio?

  And suck.

• 32:53Neil deGrasse Tyson?

  Yeah, yeah, yeah, yeah. Suck, that's the second time I'm using this word, suck.

• 32:58Neil deGrasse Tyson?

  Gravity is pulling them in.

• 32:59Paul Mecurio?

  Gravity is pulling, I'm sorry.

• 33:00Neil deGrasse Tyson?

  Bring a new sentence to your-

• 33:03Paul Mecurio?

  Wait a minute.

• 33:04Neil deGrasse Tyson?

  Saturn sucks.

• 33:05Paul Mecurio?

  Why? Because suck's not in the Oxford Dictionary, is that right? And when, do they anticipate when that might happen, that those rings disappear?

• 33:14Neil deGrasse Tyson?

  Well, so they suspected that it's a 10-million-year-or-so lifespan, which would mean, the dinosaurs, if they had telescopes, Saturn would not have rings for them. Because they were 60 million years ago. They were longer ago than Saturn's rings would have, yeah.

• 33:31Paul Mecurio?

  So the rings of elephants-

• 33:31Neil deGrasse Tyson?

  I feel sad, yeah, I'm just saying.

• 33:34Paul Mecurio?

  I'm gonna miss those rings.

• 33:36Neil deGrasse Tyson?

  In 10-

• 33:37Paul Mecurio?

  Those times we had together.

• 33:38Neil deGrasse Tyson?

  In 10 million years. Okay, next question.

• 33:41Paul Mecurio?

  Okay, here we go. This is from Carcella Banesior. I'm sorry if I'm butchering that. This is from Twitter. "Since Jupiter's 90% hydrogen, can we tell it's a failed star, if it's a failed star?"

• 33:58Neil deGrasse Tyson?

  Ooh, yes, we can tell if it's a failed star, but you won't learn that until after this break.

• 34:02Paul Mecurio?

  Wow.

• 34:03Neil deGrasse Tyson?

  See what I did there?

• 34:04Paul Mecurio?

  There you go.

• 34:04Neil deGrasse Tyson?

  Was that good? That's how the pros do it, right? Okay, when we come back, we will find out whether Jupiter was a failed star.

• 34:26Paul Mecurio?

  Thanks to the following Patreon patrons for helping us make our way across the cosmos. Tom Hernke and Jonathan Gaffers. Thanks so much, guys. And if you would like to get your very own Patreon shout-out, head to patreon.com/startalkradio and support us.

• 34:45Speaker 03

  This is StarTalk.

• 35:02Neil deGrasse Tyson?

  We're back, cosmic queries, planets, and stuff. Paul, we last left off, yes?

• 35:09Paul Mecurio?

  Yes, we had a very interesting question from Twitter, and this is from Sarahcella Banesiru. "Since Jupiter's 90% hydrogen, can we tell if it's a failed star?"

• 35:21Neil deGrasse Tyson?

  So she knows that the sun is 90% hydrogen. So these big gaseous things out there basically have their birthday elements in it. Oh, the universe's birthday elements. 90% of the universe is hydrogen. 90% of the atoms of the universe are hydrogen atoms. About 8% are helium atoms. When you see that ratio in big gaseous things, they're mostly made of stuff the universe was born with. So, if stars are made of 90% gas, and Jupiter is, could Jupiter have been a failed star? Sort of.

• 35:53Paul Mecurio?

  Why? Because it was on Dancing with the Stars?

• 35:57Neil deGrasse Tyson?

  Is that where all the failed stars go? Does that joke still have currency? People still talk about that? People who, career, they need a boost, so they go on Dancing with Stars?

• 36:05Paul Mecurio?

  I kind of think so, yeah.

• 36:07Neil deGrasse Tyson?

  I'm asked all the time to be on Dancing with Stars.

• 36:09Paul Mecurio?

  You have to go.

• 36:10Neil deGrasse Tyson?

  No, I'll tell you why not.

• 36:11Paul Mecurio?

  I want to see you in tights, in the mass, and the volume.

• 36:15Neil deGrasse Tyson?

  You want to check out my density, that's what you're saying?

• 36:18Paul Mecurio?

  But I remember talking about this on my podcast. You danced professionally, you're like a trained dancer when you're younger.

• 36:25Neil deGrasse Tyson?

  I was a performing member of three dance companies, but they were like college troops. It was not the Bolshoi.

• 36:30Paul Mecurio?

  Once you got it, you got it.

• 36:33Neil deGrasse Tyson?

  But that was a chapter of my life, long gone. I'm not thinking of my present and future and saying, "Gee, I should dance again." These are not my thoughts. When I was dancing, I was not writing books. No one was publishing my essays, okay? So, Paul, take kindly the counsel of the years gracefully surrendering the things of youth.

• 36:59Paul Mecurio?

  I think you should dance.

• 37:02Neil deGrasse Tyson?

  After all that, I just told you, that's the best you could-

• 37:04Paul Mecurio?

  Just listen to what I tell you to do, please. So, you have a, possibly a failed star, is what you're saying.

• 37:12Neil deGrasse Tyson?

  Oh, sorry, that's what we were talking about. Thank you. So Jupiter, had it been, I forgot the latest numbers on this. Had it been maybe five times more massive? Somewhere around between 5 and 10, it would have been a star. And we would have had a double-star system.

• 37:32Paul Mecurio?

  Why does that size suddenly make it a star?

• 37:34Neil deGrasse Tyson?

  Because the bigger you are, the higher the pressure is in your core. Because there's more mass, there's more weight, there's more pressure. And when you have pressure in the core, the temperature rises. And as the temperature rises, there's a threshold where you start fusing-

• 37:56Neil deGrasse Tyson?

  Nuclei in the presence of heat. Thermoneuclear fusion. That's where you get that word from. The sun is undergoing thermonuclear fusion in its core. The high pressures, high temperatures are squeezing together hydrogen atoms and out the other side comes helium atoms. And the helium atom has less mass than the hydrogen atom. Where did the mass go? E equals mc squared. It became energy and that energy is sustaining the star. Jupiter didn't have enough. Didn't hit that threshold.

• 38:30Paul Mecurio?

  And forgive me if this sounds like a silly question and I'm being serious. If Jupiter's 90% hydrogen.

• 38:37Neil deGrasse Tyson?

  Yes.

• 38:38Paul Mecurio?

  Is it just this ball of gas? Could I fly through it or would I hit?

• 38:42Neil deGrasse Tyson?

  Yeah, so there's no surface. Right, so you fly straight into it and you just keep plunging down. But you start feeling higher and higher gas pressure above you and eventually you get squashed or vaporized depending on whether you hit a hot zone sooner than a high pressure zone. So it depends on how resistant to pressure you are. That could get you to deeper, if you have a vessel, for example, that could get you to deeper places where it's even hotter. So Jupiter did get hot in its core. Oh, don't let, let's not be unclear about this. It did get hot, just didn't get hot enough to hit that threshold of thermonuclear fusion. It would have been fun to have two suns though in our solar system.

• 39:22Paul Mecurio?

  What would that have been like for us?

• 39:24Neil deGrasse Tyson?

  Bad.

• 39:26Paul Mecurio?

  A lot of sunscreen.

• 39:27Neil deGrasse Tyson?

  No, as you go around the suns, you're closer to one at one point and then not so close to the other. That can wreak havoc on the stability of your climate. Also, it wreaks havoc on the stability of your orbit. Where's your orbital allegiance today relative to yesterday? Never good for orbits. Your orbits go unstable and you fall into one of the two stars or you get flung out.

• 39:50Paul Mecurio?

  I say that all the time. It's never good for two orbits. I mean, but you know, never good for orbits.

• 39:56Neil deGrasse Tyson?

  Next question.

• 39:56Paul Mecurio?

  Next question, okay. This is Ulysses Lindblad, Twitter. Do you get high and low tide on the northern and southern poles?

• 40:07Neil deGrasse Tyson?

  Oh, very good question. You know, I never thought about that. So let me think about it now for the first time and I'm thinking no. Because the bulge, well, excuse me, you wouldn't, definitely wouldn't in the first day of spring and first day of fall. Because on those two days, the poles are sideways to Earth. And the tidal bulge is a bulge of the ocean, of the water mass of the Earth. And a tidal bulge, it bulges both towards the moon and away from the moon. So bulges in both directions.

• 40:47Paul Mecurio?

  Moving this way.

• 40:48Neil deGrasse Tyson?

  This way, correct. That's why there are two high tides. That's why there are two high tides in a day. Right? Do you ever know?

• 40:56Paul Mecurio?

  Oh, yeah, I know. It's like, we go boating.

• 40:58Neil deGrasse Tyson?

  You go boating. There are two high tides in a day.

• 41:00Paul Mecurio?

  Why, why? I don't know.

• 41:01Neil deGrasse Tyson?

  Because it has two bulges. One, so here's the moon off to the side. There's a bulge that's closest to the moon and a bulge that's opposite the moon. So you say, well, if the moon is tugging on it, how could it bulge the other way? Here's what's happening. The moon is tugging on the water and on the Earth. So it's tugging, the closest water gets pulled the most.

• 41:18Paul Mecurio?

  Which makes low tide.

• 41:20Neil deGrasse Tyson?

  Only on the sides of this because the water got sucked out of the intermediate places on Earth. The point that points towards the moon, that's closest, it feels the moon's gravity the greatest. Then it's Earth that feels it next greatest. Then there's the side of the water on the other side of the Earth that feels it the least. So there's an elongation of the entire system in the direction of the moon.

• 41:45Paul Mecurio?

  And that's.

• 41:46Neil deGrasse Tyson?

  These are called tidal forces, tidal stretching. Earth has tidal, goes through tides. They're not as high as the water, but Earth, the solid mass of Earth actually stretches in this way. So as Earth turns once a day, as Earth turns once a day, it goes through two high tides. Now, these bulges come out from one side of the Earth and the other. Okay. So the size of your tides are affected by several things, but also sort of your latitude, yes, on Earth. I'm expecting that the equator will have higher range between high and low tides than other latitudes would, but there are other factors that affect it. Do you know the highest swing in tides is the Bay of Fundy?

• 42:29Paul Mecurio?

  Why?

• 42:30Neil deGrasse Tyson?

  Oh, Bay of Fundy, because there's a long, is it a fjord? It's a very long track of land that, two sides of the land that has a long, I think it's a fjord. And so what happens is it's, the tide comes in and it's, the slope is very shallow. So if the tide goes up a foot, it goes in a half a mile. It's really cool. So you can like run alongside the tide as the tide is coming in.

• 43:04Paul Mecurio?

  Because it's so shallow.

• 43:05Neil deGrasse Tyson?

  It's so shallow and so the tide, if it goes up a foot, it's going to go up a foot. But if to go up a foot means you have to go down shore a mile, that's where it's going to be when it goes up a foot. So the movement of these tides creates friction against, between the waters and the Earth. And the height of the tide, I think, is not so important in that case as much as how much the tide moves and how much friction Earth feels against it. And do you know this friction between the oceans and the tide is slowing down Earth's rotation? We're in the stuff part of this broadcast.

• 43:40Paul Mecurio?

  Why is it slowing down the rotation?

• 43:42Neil deGrasse Tyson?

  Because Earth, oh, I left something out. This tidal bulge that I said aligns with the moon? It doesn't.

• 43:50Paul Mecurio?

  Don't lie to me, man. Don't play with my.

• 43:53Neil deGrasse Tyson?

  I have to lie to begin the explanation. Otherwise it's TMI, okay? Do we understand what I just told you that the moon stretches this whole system?

• 44:03Paul Mecurio?

  First of all, stop yelling at me. No, I'm just kidding. Yes, and can I just say it quickly for my own? So we're on the East Coast, the Atlantic Ocean. So when, and we're in New York City. So when we're, when this side of the Earth that we're on is sort of aligned with the moon, that's when you're going to get low tide because it's pulling.

• 44:22Neil deGrasse Tyson?

  No, if we're aligned with the moon, it pulls it and we're going to get high tide.

• 44:25Paul Mecurio?

  I'm sorry, it's pulling, right, okay, got it, okay.

• 44:26Neil deGrasse Tyson?

  Okay, now, you want to know something interesting? When you're at the beach, we say, oh, the tide's coming in, tide's going out. That's not what's happening. The tide is just always there in space. You're on the solid Earth and you're rotating through the high and low tides.

• 44:45Paul Mecurio?

  So if I pick the spot in the ocean, the tide is always that level?

• 44:50Neil deGrasse Tyson?

  No, not a spot in the ocean. You pick a spot in line between Earth and the moon, pick that spot, that'll always be water at a certain height. It'll just be there. And so, and Earth, that whole system, and Earth is, Earth, the solid Earth is rotating in that.

• 45:06Paul Mecurio?

  And so when we're in it, it feels like high tide and we're not.

• 45:08Neil deGrasse Tyson?

  When we're in it, we say it's tide coming in and out, but it's Earth rotating into a high tide bulge and out of a high tide bulge. Yeah.

• 45:19Paul Mecurio?

  Does the water get displaced?

• 45:21Neil deGrasse Tyson?

  So it's the illusion that something's coming towards us and away from us. It is, you are rotating into it. And so now, I said it lines with the moon? It doesn't. It's ahead of the moon.

• 45:32Paul Mecurio?

  And why is that?

• 45:33Neil deGrasse Tyson?

  Because Earth is dragging the tide. This whole bulge wants to align with the moon, but Earth is not letting it. It's pulling it in front. So that, so the tidal bulge is ahead of the moon.

• 45:43Paul Mecurio?

  It's gravitational, right?

• 45:45Neil deGrasse Tyson?

  Uh, it's.

• 45:46Paul Mecurio?

  See, I didn't use the word suck.

• 45:47Neil deGrasse Tyson?

  No, no. It's the friction between Earth and all of this water that is shoving the water ahead of where the moon is. And the moon is trying to resist this by pulling, come back to me, tide. No, I'm pulling it ahead of you. This battle between Earth and the moon is slowing down Earth's rotation. It is the source of the occasional leap second that is thrown into the calendar.

• 46:14Paul Mecurio?

  Because it's slowed down by this process.

• 46:17Neil deGrasse Tyson?

  Because the moon is making the tides and the tides are resisting what Earth is trying to do.

• 46:21Paul Mecurio?

  And what would Earth be like if that did not happen?

• 46:25Neil deGrasse Tyson?

  If we didn't have tides?

• 46:26Paul Mecurio?

  If we, if it didn't get slowed down by this friction that's happening?

• 46:32Neil deGrasse Tyson?

  Uh, if we didn't get slowed down, then the duration of a day would be stable, but it's not. The length of the day is increasing, very slowly, by the, you're not going to notice it and you're not going to care. But clocks care, GPS satellites care. Those, that matters.

• 46:47Paul Mecurio?

  But a day isn't 24, every day isn't 24 hours.

• 46:50Neil deGrasse Tyson?

  No, not anymore. It's slightly longer than 24 hours. And rather than increase the length of a second, which would create its own problems, we just say, wait till that increase accumulates a second, then we just throw one in.

• 47:03Paul Mecurio?

  And that's the.

• 47:04Neil deGrasse Tyson?

  So on the leap second years, this last minute of that year has 61 seconds in it. Just to make up for things because of the tides. Because we are dragging ourselves through high tides and low tides in space.

• 47:21Paul Mecurio?

  That, this explains why I'm always late. The tides, thank you. I got to the bottom.

• 47:26Neil deGrasse Tyson?

  Paul, did we only get through four questions? We, one, a quick one, quick. Because I think we've actually run out of time.

• 47:32Paul Mecurio?

  Okay.

• 47:33Neil deGrasse Tyson?

  Let's try, I'll give a soundbite answer. Ready, give it to me.

• 47:34Paul Mecurio?

  Okay. This is from Tropical Troy 68 Instagram. Hello there, guys. I love the show. Can you tell me what US taxpayers gained by going to the moon six times from 1969 to 1972, other than a bag of rocks?

• 47:49Neil deGrasse Tyson?

  Oh, oh.

• 47:52Paul Mecurio?

  Throwdown.

• 47:52Neil deGrasse Tyson?

  Hold me back. Hold me back.

• 47:59Paul Mecurio?

  I can give you another question.

• 48:00Neil deGrasse Tyson?

  No, I said I was only going to give a soundbite answer. Here it is. You ready? So I could speak on this for an hour, but I won't. I'm going to speak on it for one minute. When we went to the moon to explore the moon and turned around and photographed Earth, we discovered Earth for the first time. All major environmental legislation that exists in this country is traceable to the years that we were landing on the moon. We went to the moon to explore the moon and we discovered Earth.

• 48:41Neil deGrasse Tyson?

  Oh my gosh, Earth, not as your schoolroom globe showed it to you. No, not with color coded countries. No, Earth as the universe intended you to see it with oceans and land and clouds. And we're all down there together. It is the greatest of the gifts of the cosmic perspective that we have ever received. Only when the photo of Earth from the moon was published, should we say, hey, wait a minute, maybe we should ban leaded gas, maybe we should ban DDT, maybe we should clean up the Earth, maybe we should clean up the water supply, maybe we should clean up the air, maybe we should protect species.

• 49:25Neil deGrasse Tyson?

  There were some versions of those acts that existed earlier, but the comprehensive versions where everybody's behind them, that all happened, 1969, 70, 71 and 72. The Environmental Protection Agency was founded in 1970. We're still going to the moon. So I ask you, what is the universe and the cosmic perspective it provides worth to you? This has been.

• 49:59Paul Mecurio?

  I'm intrigued and frightened at the same time.

• 50:04Neil deGrasse Tyson?

  I've been your host, Neil deGrasse Tyson, Paul Mecurio, co-host. Thanks for being on, dude.

• 50:09Paul Mecurio?

  Absolutely.

• 50:10Neil deGrasse Tyson?

  As always, until next time, I bid you to keep looking up.