Cosmic Queries – Intergalactic Impacts

What happens when three black holes collide? On this episode, Neil deGrasse Tyson and comic co-host Chuck Nice explore even more cosmic collisions in space, in the quantum realm, and more!

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

• 0:01Neil deGrasse Tyson?

  Welcome to StarTalk. Your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk Cosmic Queries Edition. I got Chuck Nice with me. Can't do that without Chuck. Chuck, how you doing, man?

• 0:22Chuck Nice?

  Well, that's not true.

• 0:25Neil deGrasse Tyson?

  Oh, actually, it's not true. That's right. We've had a...

• 0:28Chuck Nice?

  You have done this without Chuck, that's for sure.

• 0:31Neil deGrasse Tyson?

  I've had guest co-hosts for Chuck. Because Chuck sometimes is a busy man, and you don't have time for us. That's how that works.

• 0:38Chuck Nice?

  Okay, well, that's not true either.

• 0:43Neil deGrasse Tyson?

  So Chuck, a little while ago, we did an entire Cosmic Queries on cosmic collisions, which is a very rich tapestry of phenomena and objects in the universe that go bump...

• 0:55Chuck Nice?

  Celestial banging.

• 0:56Neil deGrasse Tyson?

  ...in the night. And in fact, of the portfolio of public talks that I give, that is the title of one of them: Cosmic Collisions. So if a city invites me to their theater to give a public talk, and they get the list of things I can talk about, Cosmic Collisions is frequently selected in that list. And so I'm ready for anything you got.

• 1:21Chuck Nice?

  All right.

• 1:22Neil deGrasse Tyson?

  So Chuck, you solicited questions from our Patreon members? And so I guess it's all about collisions, so bring it on.

• 1:29Chuck Nice?

  Okay, let's jump right into this. This is Christopher Bax, and Christopher says, "Dr. Tyson and darling Chuck." Well, Christopher.

• 1:41Neil deGrasse Tyson?

  Thank you, Christopher.

• 1:43Chuck Nice?

  You know, you really know a way to a man's heart, Christopher, that's all. I am susceptible to flattery. Sometimes people refer to photons as not experiencing time from that photon's vantage point, the moment it's emitted from a source, and the moment it hits something are simultaneous. Does that mean that the object a photon impacts is deterministic?

• 2:12Chuck Nice?

  Let's say, for example, I see a photon from a star 1 million light years away. From my perspective, I just happened to be there when I looked up and the light hit my eye. But from the photon's perspective, it hits the lens of my eye at the exact moment it was emitted. Does that mean that I had to be in that spot at that time? Because I was predestined to be hit by that?

• 2:39Neil deGrasse Tyson?

  My voice is getting deep. He's getting deep.

• 2:42Chuck Nice?

  Yeah, he's just going off philosophical. Also, he says at the end of that, um, are you a fan of sativa marijuana? Or, no, I'm joking. I just put that. He didn't say that.

• 2:58Neil deGrasse Tyson?

  So, so if we think of photons hitting their destination as a collision, perfectly happy to think of it that way. So if you didn't happen to stand up and, and stand and look up when the photon hit your eye and you like stepped to the side, the photon would then hit the leaf or the grass or the mountainside or the, the beach. It'll, it'll just be instantaneous with that. So what you're thinking to yourself is that the photon, when it's emitted, sees your eye and then just goes straight into your eye in that instant. But no, 30,000, however many thousands of years do pass and things can happen before the photon hits its destination.

• 3:42Neil deGrasse Tyson?

  So, so I guess what you're wondering is, does the photon have an awareness, an advanced awareness of where it's going to hit since no time elapses? That's kind of what you think, what he's saying there, I think. Is that what you think, Chuck?

• 3:59Chuck Nice?

  Yeah, I think so. I mean, that's one version of predestination. I mean, the other predetermined outcome would be that it was set before the photon left its origin.

• 4:12Neil deGrasse Tyson?

  Yeah, yeah, but I'm just saying, so, so the three of us are here looking up and we're on some kind of rotating wheel, right? And so, okay, who's going to get the photon and who's not? And the photon already knows at the moment it was emitted, whose eyeball it's going to go into.

• 4:32Neil deGrasse Tyson?

  So that's a way, I have to think about that some more.

• 4:34Chuck Nice?

  Yes, because at, as far as the photon is concerned, that's the way it has to be, because it's, it actually comes into existence at the time

• 4:44Neil deGrasse Tyson?

  That it gets absorbed.

• 4:45Chuck Nice?

  Reaching its destination.

• 4:47Neil deGrasse Tyson?

  Correct, correct. And if that's

• 4:49Chuck Nice?

  So it has to be that way for the photon.

• 4:51Neil deGrasse Tyson?

  If that's the case, so I have to, I have to think about that some more.

• 4:56Chuck Nice?

  Yeah.

• 4:56Neil deGrasse Tyson?

  It's a good one. All right.

• 4:58Chuck Nice?

  That's a, yeah, I mean, because that's, I mean, it's truly philosophical in nature. But what he made me think about

• 5:04Neil deGrasse Tyson?

  Yeah.

• 5:05Chuck Nice?

  is, I mean, actually, what you made me think about in reference to his question, are all the photons that lose out on being seen because they land on some stupid beach.

• 5:22Neil deGrasse Tyson?

  Okay.

• 5:24Neil deGrasse Tyson?

  Well, I lament, I, I, I wrote about this long ago because I felt it. I was on mountain tops getting data for my PhD. And I thought to myself, the photons that come to my telescope and go into my detector and go into my data are serving to have the universe understand itself.

• 5:44Chuck Nice?

  Right.

• 5:44Neil deGrasse Tyson?

  Because we humans are products of this universe. And what if that photon missed my telescope and just slammed into the side of the mountain? What a, what a wasted trip.

• 5:56Chuck Nice?

  Yes, that's what I'm saying.

• 5:58Neil deGrasse Tyson?

  That's sad.

• 6:00Chuck Nice?

  I just traveled 40,000 years to be a part of Driftwood?

• 6:07Neil deGrasse Tyson?

  Driftwood, Driftwood. Or you're on a beach and you hit someone's buttocks who's, who's sunbathing, you know?

• 6:13Chuck Nice?

  Oh, man. Yeah, exactly. It's like I spent all this time. I passed, I passed Neptune, I passed Uranus, only to hit your ass.

• 6:28Neil deGrasse Tyson?

  Pass Uranus to hit your ass?

• 6:32Neil deGrasse Tyson?

  No, so, so I, um, yeah, I think about the photons. And how about the ones that miss Earth entirely and just keep moving through space?

• 6:40Chuck Nice?

  Keep going.

• 6:41Neil deGrasse Tyson?

  Rest of space is empty. And so the universe is filled with photons crisscrossing through the night and the day. And so, yeah, I have to think more deeply about the life of a photon. And I picked that one back up.

• 6:55Chuck Nice?

  I gotta just pick up on that. So two light sources, two photons in the emptiness of space.

• 7:03Neil deGrasse Tyson?

  Yes.

• 7:05Chuck Nice?

  Crisscross.

• 7:06Neil deGrasse Tyson?

  Yeah.

• 7:07Chuck Nice?

  But they can't hit each other.

• 7:09Neil deGrasse Tyson?

  No, they can, they can cross each other. They're just waves at that level. So here's the thing, I got into a Twitter fight, mild Twitter fight with Brian Cox, who's kind of my counterpart over in the UK. Not Brian Cox, the actor, but Brian Cox, the physicist. He's done a lot of PBS, BBC TV. In fact, he's on tour. He occasionally tours through the United States. He's got a whole universe show, okay? But the, so I got into a Twitter fight because I said that lightsabers in Star Wars,

• 7:41Neil deGrasse Tyson?

  you know, they could cut things and do damage if they're high enough power, but they can't bounce off each other because light waves pass through. Columns, there's like two lasers, they'll just pass through each other. It's not like, like, uh,

• 7:57Neil deGrasse Tyson?

  it's, it's not like Ghostbusters, right?

• 8:00Chuck Nice?

  Ah, don't cross streams.

• 8:02Neil deGrasse Tyson?

  Don't cross the streams, okay? No, it's whatever, we don't know what happens if that's what happens in Ghostbusters, but it's not a problem with light beams. So here's my point. If, uh, so I say this and then, and then Brian Cox comes up, well, actually, if the, if they're made of gamma rays, the gamma rays, two gamma rays, have a probability of interacting with each other and not passing through each other. They have high enough energy to do this. And then you could simulate what could be a sort of a bouncing effect between two swords, two laser swords. And so I had to, I conceded on international Twitter that I got out geeked in that, in that tweet.

• 8:42Chuck Nice?

  That's cool.

• 8:43Neil deGrasse Tyson?

  Yeah, so not all photons will, will.

• 8:45Chuck Nice?

  Wouldn't you both be fried, wouldn't the two sword fighters be fried?

• 8:48Neil deGrasse Tyson?

  From the gamma rays, well, they'll turn into the Hulk. You know, there's other issues. Yeah, yeah, yeah. That's the least of my concerns about the absence of physics in Star Wars. Just make that clear. Yeah, I said, yeah, I said it.

• 9:02Neil deGrasse Tyson?

  All right, give me some more.

• 9:04Chuck Nice?

  All right, let's go with Fred Lombardo. Fred Lombardo says, "G'day, Dr. Tyson. Since your numerous references to the idea that dark matter should be called Fred, which is my name,

• 9:17Neil deGrasse Tyson?

  Oh, all right.

• 9:17Chuck Nice?

  I have thought of myself as dark matter. My question, though, since the Fred particle seems to elude scientists, is it possible that the particle is actually a particle of time itself? This would account for its making up a majority of what seems to construe the universe and explain why it, a particle, has never been found.

• 9:39Chuck Nice?

  Love the show, and please say hi to Chuck."

• 9:44Neil deGrasse Tyson?

  So a particle of time, so that's...

• 9:46Chuck Nice?

  Right.

• 9:48Neil deGrasse Tyson?

  See, time is a coordinate, just as space is a coordinate. So you'd have to have analog to, is there a particle of space that can move through space the way a particle of time might move through time? And I don't think you can do that. There is the smallest unit of space, okay? It's called a Planck length. It's very small. And the smallest unit of time would be the time it takes light to cross a Planck length. So in a sense, space and time are quantized. They're effectively voxels, that's volume pixels,

• 10:32Neil deGrasse Tyson?

  voxels of space and time in the universe. But they're not separately particles in that sense. By the way, I just thought of calling them Fred only because we don't know what it is, so...

• 10:43Chuck Nice?

  We don't know what it is.

• 10:44Neil deGrasse Tyson?

  That's all. It's really, you know what it literally is? It's dark gravity. To call it dark matter implies it's matter, and we don't even know that. It's a good bet that it would be. If you're a betting person, that's where the odds are in your favor, but... So no, I'm not voting for a particle of time. What's that movie? There was a movie where you could collect time and then add it to your life?

• 11:08Chuck Nice?

  Yes, that was with Justin Timberlake.

• 11:11Neil deGrasse Tyson?

  Yeah, Justin Timberlake, that's correct.

• 11:12Chuck Nice?

  I forget the young lady's name. But yeah, you could buy time. Time was the commodity.

• 11:19Neil deGrasse Tyson?

  Time was the commodity.

• 11:20Chuck Nice?

  There was nothing else of value in the world except time.

• 11:22Neil deGrasse Tyson?

  Right.

• 11:22Chuck Nice?

  And it was the currency for everything.

• 11:24Neil deGrasse Tyson?

  Right, right, right.

• 11:25Chuck Nice?

  Yeah.

• 11:25Neil deGrasse Tyson?

  So.

• 11:26Chuck Nice?

  And the rich people, and the rich people had all of it. And the more time you had, the longer you lived.

• 11:30Neil deGrasse Tyson?

  Well, don't the rich people have, always have more of everything that everyone else wants? Otherwise, what's the point of being rich?

• 11:36Chuck Nice?

  That's so true. That's it. That's it. That's.

• 11:40Neil deGrasse Tyson?

  That's all I'm saying. So, so in that one, maybe you can think of those as time particles. I have a time particle and I hand it to you. And then you accrue the time. But it's not clear why that would have anything to do with, with.

• 11:54Chuck Nice?

  Dark gravity?

• 11:55Neil deGrasse Tyson?

  With dark gravity, correct. Or even the acceleration of the universe. So, yeah. There you go. But good try.

• 12:01Chuck Nice?

  Okay, well, there you go.

• 12:02Neil deGrasse Tyson?

  Yeah, yeah, yeah.

• 12:02Chuck Nice?

  Hey, Dan, nothing wrong with trying to find a little self-hype in dark gravity, Fred.

• 12:09Neil deGrasse Tyson?

  Fred.

• 12:09Chuck Nice?

  Nothing wrong with, nothing wrong with that, Fred.

• 12:12Neil deGrasse Tyson?

  And did you know, there was, was it, there was a DC superhero? Briefly introduced, I think it was DC, not Marvel, who's, who's named Fred. And that's his sort of regular name, but his superhero name was Dark Matter. And so.

• 12:30Chuck Nice?

  I didn't know.

• 12:32Neil deGrasse Tyson?

  You didn't know that?

• 12:32Chuck Nice?

  You're just making that up.

• 12:33Neil deGrasse Tyson?

  I'm telling, I'm telling you, I'm telling you. In my astronomy bizarre public talk, I, I talk about Fred, the dark matter. By the way, I didn't discover that myself. Someone heard me calling dark matter Fred. They say, did you know? And then they showed me a picture.

• 12:49Chuck Nice?

  And they showed you the picture?

• 12:50Neil deGrasse Tyson?

  It's Fred with all of the properties, you know? It's like, what are your parameters? You know, your origin story? What are your powers? What are your power limits? And what's your civilian name? This is, dark matter civilian name is Fred.

• 13:02Chuck Nice?

  His civilian name is Fred. Wow.

• 13:04Neil deGrasse Tyson?

  Right.

• 13:04Chuck Nice?

  First of all, that has to be DC.

• 13:08Neil deGrasse Tyson?

  It's probably DC, because he's got, they've got a.

• 13:10Chuck Nice?

  Yeah, because.

• 13:11Neil deGrasse Tyson?

  A civilian name, right.

• 13:13Chuck Nice?

  Yeah, because Marvel would never make any superhero named Fred.

• 13:20Chuck Nice?

  And no offense to you, Fred, but... That's cold. No, take that back. Yeah. No, take that back. No, because, let me tell you, nobody goes just like, "Help me, Fred!" No, no, his superhero name is Dark Matter, that's my point. Oh, oh, yeah, well, still, even, even still, I mean, like, think of it. Let's think of it now for a second. Help me, Fred! All right, but, no, think of this. Bruce Wayne. Yeah. Clark Kent. Yeah. Peter Parker. All right. Fred Farter? Far- Fred, Fred, Fred, what? Fred? No, Fred doesn't work. All right, all right. Fred doesn't work. Sorry, anyway.

• 14:01Chuck Nice?

  We'll send you complaints to the, to the Marvel complaint chat room, right, okay. Now, Marvel, they have good, they have good names. Okay, here we go. This is Justin Hanson. Greetings, esteemed Dr. Tyson. My son Tucker, who just turned 11, recently asked me whether reducing the temperature of a radioactive element to absolute zero would give the appearance of the half-life being reduced due to relativistic effects. You are lying. No 11-year-old asked this damn question. Who the hell you think you fooling? Just say you wanna know this, Justin. That's all you gotta do. Hey, Dr. Tyson. Pass it off on his kids. Yeah, I got a, I got a question I was thinking about for a long time.

• 14:44Chuck Nice?

  You know, it has to do with absolute zero and radioactive element. Dude, you gotta be kidding me. Anyway, 11-year-old, 11-year-old Tucker wants to know. Okay, 11-year-old Tucker is the next superhero nemesis. Yes. Super, superhero, right? What is he building in his basement?

• 15:03Neil deGrasse Tyson?

  All right, we have to, we must find that out immediately. Send authorities.

• 15:06Chuck Nice?

  And it ain't good.

• 15:09Chuck Nice?

  I'll tell you this right now. If Tucker wants to know if a radioactive element at absolute zero would give the appearance of the half-life being reduced due to the relativistic effects, you know.

• 15:22Neil deGrasse Tyson?

  Okay.

• 15:22Chuck Nice?

  I say move out now. Blow up your house.

• 15:27Neil deGrasse Tyson?

  Move out now.

• 15:28Chuck Nice?

  Yeah, move out now. Cause Tucker's blowing that joint.

• 15:31Neil deGrasse Tyson?

  While you can.

• 15:32Chuck Nice?

  Yeah, there you go.

• 15:33Neil deGrasse Tyson?

  All right, so that's an excellent question. So as, as you know, everything slows down as you drop the temperature of things. But when I say everything, everything chemical slows down.

• 15:45Neil deGrasse Tyson?

  Chemical things slow down. So the rate at which chemical reactions under, uh, unfold, it goes to about half the rate for every 10 degrees Celsius. So that's why, for example, it's important that your refrigerator is as cold as you can get it, but not freezing. So that whatever bacteria are growing in your food that would ultimately turn it green and smell nasty, you want to delay that. All right? It's not that food is good until it's nasty. The food is systematically getting nasty until it hits some nose threshold or color threshold that you have held for it.

• 16:25Chuck Nice?

  Right. Unless it's avocado, in which case five minutes is all it will last, no matter what.

• 16:30Neil deGrasse Tyson?

  Until it turns brown on the top.

• 16:31Chuck Nice?

  Right. You, you take it out five minutes later, it's a rotten mess.

• 16:35Neil deGrasse Tyson?

  No, you put some, put some lemon juice on it. Lime juice is good. It'll work.

• 16:38Chuck Nice?

  All right, I'm gonna try that.

• 16:39Neil deGrasse Tyson?

  What do you try? You didn't know this?

• 16:41Chuck Nice?

  No, I didn't know that.

• 16:42Neil deGrasse Tyson?

  Dude.

• 16:43Chuck Nice?

  Is that for real?

• 16:43Neil deGrasse Tyson?

  Have you never met a Mexican in your life?

• 16:47Neil deGrasse Tyson?

  You gotta get out more.

• 16:49Chuck Nice?

  You know what? Now you're embarrassing me because I'm gonna tell you the truth. I don't know any Mexican people.

• 16:54Neil deGrasse Tyson?

  You don't actually don't know any Mexicans?

• 16:57Chuck Nice?

  I'm in New York, man. All my friends are Puerto Rican.

• 17:00Neil deGrasse Tyson?

  Okay, that's true. Yeah.

• 17:02Chuck Nice?

  My friends and my family. I got friends in my family. They're all Puerto Rican or Dominican. If they look like me, they're Dominican.

• 17:08Neil deGrasse Tyson?

  All right, all right. So, so for every 10 degrees, so that's why food spoils faster if it's not in the refrigerator. You put it in the refrigerator, it delays it, but it will all still go bad. All right, according to this calculation, for every 10 degrees Celsius, it doubles the rate at which something will happen. Or if cooler, it'll have the rate. Keep doing this down all the way to absolute zero. You could basically keep food forever, forever in terms of bacteria that would be growing on it. You have other issues related to the molecular integrity of the food itself. So it can start losing its texture, but that's not because bacteria we're eating it. It's because the molecules themselves are unstable.

• 17:53Neil deGrasse Tyson?

  Here's the point. The moment you go nuclear, then all the things that apply to atoms and molecules no longer apply. Whole other sets of forces dominate in the nuclear regime. And so if you cool things, the nucleus done give a rat's ass. It will still decay at exactly the rate that you had measured for it at any other temperature. If you want to slow down the rate, what you do is you speed up the molecule.

• 18:22Chuck Nice?

  Ooh, okay.

• 18:25Neil deGrasse Tyson?

  You speed up the decaying particle. Yeah, you speed it up. Put it in a particle accelerator, send it nine tenths the speed of light, 99/100 the speed of light. And it will slow down the decay rate by the exact amount predicted by Einstein's special theory of relativity.

• 18:43Chuck Nice?

  Aha, because anything moving at the speed of light, time itself slows down for that.

• 18:49Neil deGrasse Tyson?

  Well, at the speed of light, it stops. So you get closer to it.

• 18:51Chuck Nice?

  That's what I'm saying. The closer you get to the speed of light, the more time slows down.

• 18:54Neil deGrasse Tyson?

  It's not just the physical watch that, you know, the timepiece that the particle's wearing on its wrist. It's everything about it.

• 19:00Chuck Nice?

  It's everything, right.

• 19:01Neil deGrasse Tyson?

  Everything, including its very nature, this probabilistic thing that it will decay.

• 19:06Chuck Nice?

  And that's why you say it's time itself that's slowing down, not...

• 19:10Neil deGrasse Tyson?

  Anything itself.

• 19:11Chuck Nice?

  It's not the measurement itself. It's the thing.

• 19:14Neil deGrasse Tyson?

  The thing itself. So you're gonna look at your clock and you slow down, your brain slows down, the clock slows down. You don't know anything is slowing down.

• 19:21Chuck Nice?

  You don't know anything has slowed down.

• 19:22Neil deGrasse Tyson?

  The particle has no idea that it took, quote, "longer" for it to decay in its own reference frame. But to our reference frame, it takes longer. So if you want to relativistically affect particles that are decaying with half-lives, you just simply accelerate them, or put them in a very different gravity field. That'll slow them down, too.

• 19:42Chuck Nice?

  Slow them down, too. Wow. Okay. Hey, "Tucker," air quotes, "Tucker," let me just say, buddy, you are, you're an amazing kid, Tucker. Okay? Let me just, you keep at this, Tucker, and whatever you're building in that basement, when you unleash it on the world, just remember, Chuck Nice is your friend.

• 20:03Neil deGrasse Tyson?

  Chuck said something nice to you.

• 20:05Chuck Nice?

  That's right. Just remember the black man who told you you were special. When you're demanding your $1 billion.

• 20:17Neil deGrasse Tyson?

  In ransom.

• 20:18Chuck Nice?

  That's right.

• 20:20Neil deGrasse Tyson?

  So Chuck, you're agreeing to be his sidekick? You're agreeing to that all the way?

• 20:25Chuck Nice?

  Yeah, listen, without a doubt.

• 20:27Neil deGrasse Tyson?

  All right. When we come back, more cosmic queries on Cosmic Collisions when StarTalk returns.

• 20:45Speaker 02

  I'm Joel Cherico, and I make pottery. You can see my pottery on my website, cosmicmugs.com. Cosmic Mugs, art that lets you taste the universe every day. And I support StarTalk on Patreon. This is StarTalk with Neil deGrasse Tyson.

• 21:09Neil deGrasse Tyson?

  Chuck, we're back. Cosmic queries on cosmic collisions of all kinds. Small, large, medium, large, universe, everything. And you got the questions from our Patreon members, so keep them coming.

• 21:22Chuck Nice?

  All right, let's do it. This is Don Lane. Sounds like a person from an old time movie. Anyway.

• 21:33Neil deGrasse Tyson?

  No, Don Lane would be a game show host.

• 21:36Chuck Nice?

  Oh, you're right. That's right.

• 21:38Neil deGrasse Tyson?

  That's a game show host name. I'm Don Lane.

• 21:41Chuck Nice?

  That's right. It's Cosmic Collisions with Don Lane. Yeah. All right, here we go.

• 21:48Chuck Nice?

  He goes, hello.

• 21:49Neil deGrasse Tyson?

  Do we watch too much TV, Chuck? Is this a problem?

• 21:51Chuck Nice?

  I don't know. It could be, you know.

• 21:55Chuck Nice?

  Don Lane says, hello, Dr. Tyson, Lord Nice. Could moons of outer planets have been born from inner rocky bodies that may have broken off of molten rocky planets in the early formation of the solar system? Could this be proven? Or would it change our current understanding of how our solar system was formed? So.

• 22:19Neil deGrasse Tyson?

  I love it. I love it. I love it. Okay, so let's look at the solar system for the moment. Only once we had sufficient computing power were we able to show. Because we started saying, oh, our solar system is probably representative. And we have some small rocky planets up close and some big gaseous ones far out and some other gaseous ones a little farther out and some comets and asteroids. Why think that we look different, right, as a first pass? When we started collecting data on exoplanets, oh my gosh. Oh, there's like a Jupiter orbiting as close to its host star as Mercury is to our sun or even closer. And there's all kinds of variation that no one expected.

• 23:03Neil deGrasse Tyson?

  Okay, so all we can say is that there is no standard solar system, star system. That first. Second, when our computer models got good enough, we would start, we would.

• 23:15Neil deGrasse Tyson?

  Create solar systems, you'd say, okay, let's start with thirty planets and see what happens. Oh, they settle out. Some planets get swung into the sun, others get eaten by the bigger planets, and others settle peacefully into their orbits. So it is highly likely that any star system with eight or ten planets in it started with two or three times that many objects. Okay, so, so, yes. Now, if you take that down to a moon system, like Jupiter, and I lost count of how many moons it has, sixty, I don't remember.

• 23:52Chuck Nice?

  Wow.

• 23:53Neil deGrasse Tyson?

  There are things you, yeah, it's a ton of moons. There are things you can know. If the moon is, it looks like an Idaho potato.

• 23:59Chuck Nice?

  Right.

• 24:00Neil deGrasse Tyson?

  Then it was never big enough.

• 24:04Chuck Nice?

  Mm-hmm.

• 24:05Neil deGrasse Tyson?

  Or its gravity to shape it into a sphere.

• 24:08Chuck Nice?

  Okay, right.

• 24:09Neil deGrasse Tyson?

  Okay, because.

• 24:10Chuck Nice?

  Could it, could it, I'm just, just following up. Could it have just been captured by that orbit?

• 24:15Neil deGrasse Tyson?

  Yeah, no, yes, but wherever it formed, I'm just saying, it was never big enough to make a sphere out of itself. So it stayed as a craggy chunk of rock.

• 24:23Chuck Nice?

  Okay, gotcha.

• 24:24Neil deGrasse Tyson?

  That's right. Second, if you do see craggy chunks of rock out there in orbit, should we call it a moon? There's a lot of stuff, like, for example, Mars has, how many moons, do you know? How many moons Mars has?

• 24:36Chuck Nice?

  I don't, I.

• 24:37Neil deGrasse Tyson?

  It has two moons. It has two moons, Phobos and Deimos, and they are the lamest moons I have. No, they look like Idaho potatoes. One is the size of Manhattan, right? It's like, no, no, don't make me call these moons. I'm sorry.

• 24:51Chuck Nice?

  Why are you moon shaming Mars, man?

• 24:53Neil deGrasse Tyson?

  Moon.

• 24:54Chuck Nice?

  Ah, go on, that's, that's cold.

• 24:57Neil deGrasse Tyson?

  Casting shade on Mars's moons. No, they, no, if I gotta be, you know, I know I have some history there with Pluto and stuff, but Pluto was at least big enough to be a sphere, all right?

• 25:09Chuck Nice?

  Right.

• 25:09Neil deGrasse Tyson?

  As is its moon, its biggest moon, Charon, was big enough to be a sphere. So there's the sphere club, and then there's the craggy chunks of rock club. And there's a very clear distinction between the two of them. So things you can learn when you see moons around other planets is, well, was it, is it massive enough to have made it into a spherical shape? If it's craggy, it's probably a chunk broken off of some other larger thing that was a sphere. Okay? In a collision. So that's another thing you can tell. And also, there are some moons where one half of the moon looks really different from the other half. Because something collided into that half and then took its own shape relative to the side

• 25:53Neil deGrasse Tyson?

  that is 180 degrees away. And a third kind of moon, forgive me, I forgot the name, the famous moon, where it looks like some piece of other asteroid collided and got stuck in it. Because if you look at the terrain, it's really, really, really different over in one section compared with another section. And it looks angular and it's like somebody just mashed it in there. And so there's a lot to learn from the topography of moons, provided they don't have weather systems that erase the record of the collisions you experienced in life. So you take a look at the surface of the moon, it's been hit by some meteors, right? How about Earth? How many craters have you seen on Earth?

• 26:37Neil deGrasse Tyson?

  A few, all right? But we're right next to the moon in the, in the, in the stream of impactors. Were it not for our atmosphere and our weather and other erosive corrosive forces, we would look just like the moon.

• 26:53Chuck Nice?

  Well, thank God that we have those weather and atmosphere.

• 26:58Neil deGrasse Tyson?

  Just like the moon. You want to thank God, that's fine, because we're...

• 27:02Chuck Nice?

  I mean, I'll thank, thank atmosphere, okay?

• 27:04Neil deGrasse Tyson?

  Thank atmosphere.

• 27:05Chuck Nice?

  I'll thank atmosphere and I'll thank weather.

• 27:08Neil deGrasse Tyson?

  No, you can thank God, I don't have a problem with you thanking God.

• 27:10Chuck Nice?

  The moon is ugly. The moon's got an ugly face. That's all I'm saying, you know? The moon is, that's cosmic acne.

• 27:18Neil deGrasse Tyson?

  Acne, and we have ways of covering up the history of that, of the scars of having been slammed. So there's a whole branch of geology and astronomy that has merged as planetary geology. And these are folks who worry about this all the time. Excellent question.

• 27:36Chuck Nice?

  All right. Excellent question, man.

• 27:37Neil deGrasse Tyson?

  Keep it going.

• 27:38Chuck Nice?

  All right. Uh, this is our old buddy, Alejandro Reynoso.

• 27:45Neil deGrasse Tyson?

  Okay.

• 27:48Chuck Nice?

  Hello.

• 27:50Chuck Nice?

  I am Alejandro Reynoso. I am coming to you from Monterrey, Mexico.

• 27:58Neil deGrasse Tyson?

  Is he from Monterrey?

• 27:59Chuck Nice?

  Yeah, he's from Monterrey.

• 28:00Neil deGrasse Tyson?

  Oh, oh, cool. So it's all there. You're running the gamut there. Okay, go ahead.

• 28:05Chuck Nice?

  He says.

• 28:05Neil deGrasse Tyson?

  Monterrey with two Rs, by the way, correct?

• 28:08Chuck Nice?

  That's correct.

• 28:08Neil deGrasse Tyson?

  Yeah, yeah. Monterrey, California, I think is one R. But, okay, go on.

• 28:13Chuck Nice?

  And then he says, hello.

• 28:15Neil deGrasse Tyson?

  Stop, Chuck.

• 28:17Chuck Nice?

  Or should I say, hola?

• 28:21Neil deGrasse Tyson?

  That is not what he said.

• 28:24Chuck Nice?

  No, he says that.

• 28:27Neil deGrasse Tyson?

  Okay, go.

• 28:28Chuck Nice?

  He says, if we, uh, if we could see it, how would the collision between two black holes look like it? We actually have seen that.

• 28:39Neil deGrasse Tyson?

  Oh, yeah, yeah. Oh, no, no.

• 28:40Chuck Nice?

  But, but, but, wait, wait. Then he goes on. All right, how about three?

• 28:48Neil deGrasse Tyson?

  Some people are just never satisfied.

• 28:51Chuck Nice?

  Yeah, I love it. Oh, that's great.

• 28:55Neil deGrasse Tyson?

  Okay, you're not likely to get three things to hit simultaneously. Just you do the statistics on it. It's just not happening. You can get two objects to collide and then collide with a third object. But to have all three collide with each other at the same time is statistically sufficiently unlikely to not really want to waste your brain power on that. But we do, no, we haven't photographed the collision of two black holes, but we know exactly what it would look like because we completely know the physics and the geometry and the relativity of what's going on. And all you have to do is Google a YouTube video of the black holes that collided that LIGO observed. So what would be the search on that?

• 29:37Neil deGrasse Tyson?

  Good search for YouTube LIGO colliding black holes. Make sure it's YouTube and then it'll be a video. And so you'll see the two, and what, you'll see their effect on the stars behind them. Okay, that's where the action is because the space around the black holes are distorted. And it brings things that are in a different place in the background into a new place in the foreground. You have a completely distorted circular images of light around the black holes. It is what you see with those recently released photos of black holes. One in our own galaxy and one in another galaxy called M87. You see a ring of light and then a darkness in the center. That darkness is basically the shadow of the black hole because no light is coming from it.

• 30:22Neil deGrasse Tyson?

  And what's around it is all the light from distant beyond it that is collected into this ring, which is the effect that black holes have on their environments. So you check it out and you watch it. And then you see this ripple, which is the gravitational wave.

• 30:36Chuck Nice?

  Waves.

• 30:36Neil deGrasse Tyson?

  That got emanated on collision. And that's what we waited 1.3 billion years to detect when we finally turned on the Laser Interferometer Gravitational Wave Observatory, LIGO. Check it out. It's beautiful.

• 30:52Chuck Nice?

  That is amazing.

• 30:54Neil deGrasse Tyson?

  It is beautiful.

• 30:55Chuck Nice?

  And so now, what, let's say we turned it on right after Einstein theorized that these gravity waves would happen. Would we have then seen them?

• 31:08Neil deGrasse Tyson?

  Okay, no, no, right, right. So, so here's the thing. Einstein wrote down an equation for the stimulated emission of radiation in atoms. And it was a small paper in quantum physics and you had to, that was in 1916 or 17, and then you had to wait until 1957. So that's 40, 40 years later, where someone uses those equations to invent the laser. Okay? The L in LIGO stands for laser. Nobody's detected anything without the laser here. Okay? So Einstein predicts gravitational waves. He, he presages the discovery of the laser.

• 31:48Neil deGrasse Tyson?

  And then we use lasers to measure the existence of gravitational waves, which means Einstein was a badass. That's all. It's just pure and simple. And he got a Nobel Prize in 1921 for nothing I just said.

• 32:02Chuck Nice?

  And that's, and that's when you know you're the GOAT.

• 32:05Neil deGrasse Tyson?

  Greatest of all time.

• 32:07Chuck Nice?

  Yeah, when they, when they, yeah.

• 32:09Neil deGrasse Tyson?

  Yeah, so what we learned was, we, you know, if you turn on the machine and you discover a colliding black hole a week later, you say, boy, we got lucky, or maybe these things are happening more frequently than you previously thought. So right now, I forgot the numbers, a dozens of colliding black holes that we have data on. So yeah, had we turned it on back when Einstein did this, we would have found them. But we, where technology and computing wasn't sufficient at the time to have come anywhere near a detection, you'd have to wait most of a century. Gotta take a quick break. When we come back, the third and final segment of Cosmic Queries, Cosmic Collisions of the Star Club.

• 33:01Neil deGrasse Tyson?

  We're back, third and final segment, Cosmic Queries, Cosmic Collisions. It's one of my favorite subjects. I could talk about this forever, Chuck. I don't know how many questions we're gonna get through. And this is our second installment of Cosmic Collisions, all right?

• 33:15Chuck Nice?

  Yes.

• 33:15Neil deGrasse Tyson?

  There's probably a third one in there, but we'll give you all a break, okay?

• 33:21Neil deGrasse Tyson?

  So Chuck, I was, I was, I was, I was surfing the TV, and there you were, your smiley face on Nat Geo in Disney Plus, host of Brain Games.

• 33:32Chuck Nice?

  Brain Games on the road.

• 33:33Neil deGrasse Tyson?

  We're, we're all proud of you, Chuck.

• 33:35Chuck Nice?

  Well, thanks.

• 33:36Neil deGrasse Tyson?

  Like, you know, you're not just any random comedian out there, you, you care about being smart, and we love that. We love that.

• 33:42Chuck Nice?

  Well, thank you. And that is true. I appreciate that, yeah. All right, here we go. This is Woody. He says, hello Neil, Lord nice. You know how the melting point of water lowers under pressure? Could two bodies of ice join together in a collision? And what kind of force would it need to make that party trick by whacking the joining ice cubes? I did try clapping ice a few times while writing this, and no, it did not work.

• 34:13Neil deGrasse Tyson?

  Yeah, it doesn't work. Woody did the experiment in anticipation of-

• 34:19Chuck Nice?

  This is not a question, he's calling you for confirmation.

• 34:24Neil deGrasse Tyson?

  Confirmation of his experiment. Alright, so, a fully solid object occupies space that cannot be encroached upon unless something changes about that body. Now, we talked about this before with ice. Ice, when you freeze water, it expands, right? So, how do I compress an ice cube back to its original volume? You can't unless the ice melts under pressure and becomes water again.

• 35:00Chuck Nice?

  Right.

• 35:01Neil deGrasse Tyson?

  So, you can't shrink the size of ice without ice having to completely change its molecular configuration, okay? From a lattice for the ice down to a fluid, which is then water. So, no, you can't take two ice cubes and just merge them into one object. That does not work. But that's true for any solid, homogeneous object. By the way, if the object has air bubbles in it or air holes, yeah, you can sort of squeeze things in to that, for sure. But if it's a uniform, solid object, it's not happening.

• 35:36Chuck Nice?

  There you have it, my friend, Woody. You have your confirmation.

• 35:40Neil deGrasse Tyson?

  Yeah, and you did the experiment. I'm delighted by the experiment.

• 35:43Chuck Nice?

  It was a success, bro.

• 35:44Neil deGrasse Tyson?

  By the way, there's some things you can try to squeeze them together, and they won't intersect, but they'll flatten, right? If I take two sort of small cubes of gold, and I try to squeeze them, I won't succeed unless the gold has permission to flatten in all directions. And on doing that, you can flatten two things if you squeeze them, sure.

• 36:06Chuck Nice?

  Right. Okay.

• 36:08Neil deGrasse Tyson?

  But the total volume of what you flattened is the same. Just so you know.

• 36:12Chuck Nice?

  Exactly.

• 36:13Neil deGrasse Tyson?

  Yeah.

• 36:13Chuck Nice?

  Right, okay. So, this is Amanda, uh, who says, "Do any of these collisions show any type of light when they happen? I know that there's a lot of light being shown either by stars or implosions, explosions that have already happened years ago, but maybe, and maybe even millennia ago."

• 36:35Neil deGrasse Tyson?

  Ooh, ooh, I love it, I love it, okay. So, uh, generally if you have a collision, there's a lot of energy that has to manifest in some way. When you're manifesting energy, often that energy comes out in the form of light of some kind. And light can be any manner, any combination of the electromagnetic spectrum. If any of that comes out as visible light, you will see a flash. There are people who have made a cottage industry of staring at the unilluminated segment of the moon on any given night. Okay, so let's say it's a half moon in the sky. They put their telescope on the half that's not lit,

• 37:19Neil deGrasse Tyson?

  and they carefully look for flashes of light.

• 37:22Chuck Nice?

  And that's an impact?

• 37:24Neil deGrasse Tyson?

  That's a, that's an asteroid impact on the surface of the moon. You're not gonna notice it in the lit side because it's too bright. All right, so there's an entire cottage industry of people who do this. All right, and, and that impact, where does the kinetic energy of the object goes? It goes back into the object. We discussed this in part one of Cosmic Collisions, I think. Did we do that, or is that in a explainer?

• 37:46Chuck Nice?

  What?

• 37:46Neil deGrasse Tyson?

  It's all one memory to me now.

• 37:48Chuck Nice?

  Yeah.

• 37:49Neil deGrasse Tyson?

  Uh, the collision of a high-speed impact, where all the energy goes back into the object.

• 37:53Chuck Nice?

  Absolutely.

• 37:54Neil deGrasse Tyson?

  So if you do that, then it explodes. If that's sufficient energy, uh, a lot, like I said, a lot of that energy goes into infrared, just to heat, and also to visible light. Now, here's something interesting, okay? Uh, you know what happens if an airplane goes through the air faster than the speed of sound? You get a what?

• 38:13Chuck Nice?

  You get a boom.

• 38:14Neil deGrasse Tyson?

  A sonic boom, okay.

• 38:16Chuck Nice?

  Sonic boom.

• 38:16Neil deGrasse Tyson?

  Okay, so now, what happens if a particle travels through a medium faster than the speed of light?

• 38:26Chuck Nice?

  Um, the entire universe implodes on itself.

• 38:30Neil deGrasse Tyson?

  So here's the thing.

• 38:31Chuck Nice?

  And we all get sucked into oblivion.

• 38:34Neil deGrasse Tyson?

  Here's the thing, light moving through transparent objects other than a vacuum travels slower than the speed of than the speed of light in a vacuum. Did you know that in diamond, which is like one of the densest transparent substances, light travels at forty percent of its speed in a vacuum.

• 38:57Chuck Nice?

  Oh, so diamonds are the brakes of light.

• 39:01Neil deGrasse Tyson?

  Yes, they they put on brakes.

• 39:02Chuck Nice?

  Brakes for light.

• 39:03Neil deGrasse Tyson?

  To slow them down. And the slower something moves in the medium, the more it refracts when it bends going through it. The bigger is that angle. So what makes diamonds sparkle is light comes in in one place. It multiply internally refracts and pops out another place. So it looks like the diamond is sort of self luminous, even though you you don't think you had anything to do with that.

• 39:34Chuck Nice?

  Right.

• 39:35Neil deGrasse Tyson?

  So so now, when you have a particle that goes through a medium and you accelerate it faster than the speed of light in that medium, it creates a flash of light. And it was discovered by a Russian called Shereenkov. It's called Shereenkov radiation.

• 39:51Chuck Nice?

  It's a light boom.

• 39:53Neil deGrasse Tyson?

  A light boom. Yes, not a sonic boom.

• 39:55Chuck Nice?

  Not a sonic boom, but a light boom. That's so cool.

• 39:59Neil deGrasse Tyson?

  Correct.

• 39:59Chuck Nice?

  That is, I just love the diamond little fat toy.

• 40:03Neil deGrasse Tyson?

  Yeah, yeah, so all of this. Yeah, yeah. So if you would if you were to put particles through um, a diamond, you get that effect at only forty percent the speed of light. And just a just a a fast fact here, the light actually doesn't slow down.

• 40:19Chuck Nice?

  Okay.

• 40:20Neil deGrasse Tyson?

  Okay.

• 40:21Chuck Nice?

  Okay, we're getting creepy now. This is cool.

• 40:24Neil deGrasse Tyson?

  Okay. Okay, so let's say you're trying to get from one side of a party to the other and it's crowded.

• 40:30Chuck Nice?

  Okay. Right.

• 40:31Neil deGrasse Tyson?

  So what happens is you bump into somebody. So pardon me, excuse me. And then in the space between you and the next person, you go at the speed of light. But then you hit the next, oh, pardon me, excuse me, and then you go again. Okay, so when the light is interacting with each of the particles in the lattice.

• 40:50Neil deGrasse Tyson?

  It has to get through that particle. And so that takes time. Whereas when it's between the particles in the lattice, it's moving at the speed of light. So you add it all up. There's a net slowdown before the beam comes out the other side.

• 41:03Chuck Nice?

  Ah, I got you. I got, it's like hurdling.

• 41:07Neil deGrasse Tyson?

  Oh, yeah, okay.

• 41:09Chuck Nice?

  It's like a hurdler.

• 41:10Neil deGrasse Tyson?

  Hurdler. They're probably going their slowest going over the hurdle.

• 41:14Chuck Nice?

  Jumping over the hurdle. That's right. But then they speed right back up.

• 41:17Neil deGrasse Tyson?

  Speed right back up.

• 41:17Chuck Nice?

  That's very cool. Either that or a diamond is just, you know, just like, slow down, baby.

• 41:24Neil deGrasse Tyson?

  It's got the music.

• 41:27Chuck Nice?

  Why are you in such a hurry?

• 41:30Neil deGrasse Tyson?

  By the way, it's too much like going into the earth's atmosphere, from the atmosphere into water and water into glass, glass into diamonds.

• 41:38Chuck Nice?

  So any, any see-through medium or?

• 41:41Neil deGrasse Tyson?

  Any, any see-through medium, correct.

• 41:42Chuck Nice?

  Cool, man.

• 41:43Neil deGrasse Tyson?

  You got it.

• 41:43Chuck Nice?

  All right, here we go.

• 41:44Neil deGrasse Tyson?

  We've got one more question. Time for one more question. Make it a good one.

• 41:48Chuck Nice?

  All right, all right. Here we go. Elaine in the stars. That's the name.

• 41:53Neil deGrasse Tyson?

  Oh, A L A I N?

• 41:54Chuck Nice?

  Yes.

• 41:55Neil deGrasse Tyson?

  Then it's A- Alain, Alain.

• 41:58Chuck Nice?

  No, A L L A I N. Elaine.

• 42:01Neil deGrasse Tyson?

  Oh, Alene, Elaine, Elaine, okay.

• 42:03Chuck Nice?

  Yeah. Hi, Dr. Tyson, Lord Nice, Elaine from Montreal, Canada here. Uh, can a meteor impact create enough energy to spontaneously create particles? Thank you, Elaine.

• 42:18Neil deGrasse Tyson?

  Oh, yeah, uh, no. No, that's, it's all, the energy of an impact, as, as ferocious as it is, is not sufficient to influence atoms. Okay, it's all, stuff will break apart. You'll lose your molecules. You might even ionize some atoms. But the nucleus itself is way out of reach of the energetics of a, of a, of a mere meteor impact. So, yeah, the regimes of the universe are very distinct and separate. By the way, that's why we can say with confidence, you know, in the early days, when we said, oh, my gosh, there's such a thing as an atom, and we found electrons. Going around a nucleus, maybe it's just a small version of a solar system.

• 43:02Chuck Nice?

  Right.

• 43:03Neil deGrasse Tyson?

  And maybe it's just that all the way down and all the way up. Wouldn't that be cool, like a nested doll? And then we went down there and we even called the electrons in their path around the nucleus, we call them orbitals.

• 43:16Chuck Nice?

  Right.

• 43:17Neil deGrasse Tyson?

  Okay, orbitals. All right, we got the word from solar systems. So you go down there and you find out, no, gravity has nothing to do with what's going on. It's got nothing to do with Newton, has to do with quantum physics, and all the forces are different, and no, they're not analogous at all. And so same when you go very large. When you go very large, certain forces no longer manifest in the same way. So you can't just scale things and claim to get all, everything in the same way. It doesn't work that way.

• 43:48Chuck Nice?

  Wow, look at that. That's, that's really, you know, the universe is a tricky little something.

• 43:53Neil deGrasse Tyson?

  It's a tricky, it's tricky. It would've been too easy if everything just scaled, right?

• 43:58Chuck Nice?

  Yeah.

• 43:58Neil deGrasse Tyson?

  Yeah, that'd be just way, way too easy. Yeah, but it's not that. It's harder, which means physicists basically have jobs.

• 44:09Chuck Nice?

  It's the trickiness that keeps us employed.

• 44:11Neil deGrasse Tyson?

  Exactly, exactly. So Chuck, that's all we have time for, and so we gotta call it quits there. Always good to have you, man.

• 44:18Chuck Nice?

  Always a pleasure.

• 44:19Neil deGrasse Tyson?

  This is StarTalk Cosmic Queries. Collisions Edition, our second installment. We'll probably do more, but we'll give you a break from it until, until you're feeling it and we start getting requests. "I need more collisions, give them to me." And we'll be there for you on StarTalk. You go to Graff Tyson, keep looking up.