Pod Insights StarTalk Podcast Cosmic Queries: Answers at the Speed of Light About this episode Join us for another episode of Cosmic Queries, where astrophysicist Neil deGrasse Tyson answers fan questions about light, energy and the universe as fast as comic co-host Leighann Lord can ask them.
Transcript Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
0:01 Neil deGrasse Tyson? Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now.
0:21 Neil deGrasse Tyson? This is StarTalk Radio. I'm your host Neil deGrasse Tyson. I'm your personal astrophysicist. I hail from New York City where I serve as Director of the Hayden Planetarium of the American Museum of Natural History and you're all invited. I got with me in studio here in New York, Leigh Anne Lord. Leigh Anne, welcome back.
0:41 Speaker 01 Thank you.
0:41 Neil deGrasse Tyson? Love having you on the show.
0:43 Speaker 01 Good to be here.
0:44 Neil deGrasse Tyson? And this is the cosmic queries part, the cosmic queries sector of the universe, I'd like to think. And we've called questions submitted to us on, in all of our social media.
0:57 Speaker 01 Yes.
0:57 Neil deGrasse Tyson? Twitter, on our Facebook page.
0:59 Speaker 01 Email.
1:00 Neil deGrasse Tyson? Email and on StarTalkRadio.com. And so this is a hodgepodge, I think.
1:05 Speaker 01 Yes.
1:05 Neil deGrasse Tyson? And I haven't seen them and you've collected them and you're gonna hand them to me.
1:09 Speaker 01 Yes.
1:09 Neil deGrasse Tyson? And if I don't know the answer, I'll just say, "I have no idea."
1:12 Speaker 01 Well, I can be honest right up front. I have no idea.
1:15 Neil deGrasse Tyson? So let's do this.
1:16 Speaker 01 All right.
1:16 Neil deGrasse Tyson? Go.
1:17 Speaker 01 We have a question and email that came from James Isaac Dagenhart. And he says, "I have read about something called Modified Newtonian Dynamics," he reads a lot, "that was introduced as being a possible model that doesn't presume the existence of dark matter. Does this have any credence or is this pseudoscience sensationalism?"
1:37 Neil deGrasse Tyson? Man, what an erudite question.
1:40 Speaker 01 Yes.
1:40 Neil deGrasse Tyson? Modified Newtonian Dynamics, that's otherwise known in the trade as MOND.
1:44 Speaker 01 Okay.
1:45 Neil deGrasse Tyson? MOND, Modified Newtonian Dynamics.
1:48 Speaker 01 And would that be an acronym?
1:50 Neil deGrasse Tyson? Yes, an acronym. When letters come together and you can pronounce them, right? But the CIA is not an acronym unless you said CIA. We actually spell out the letters.
2:01 Speaker 01 Okay.
2:01 Neil deGrasse Tyson? Yeah, IBM, not an acronym. Just putting that on the table.
2:04 Speaker 01 Got it.
2:05 Neil deGrasse Tyson? So, so what does he want to know? Oh, so... People don't like explaining things that we don't understand by other things that we understand less.
2:16 Speaker 01 Okay.
2:16 Neil deGrasse Tyson? So the dark matter problem in the universe where there's six times as much gravity out there than matter enough to account for it.
2:26 Speaker 01 Right.
2:27 Neil deGrasse Tyson? All right.
2:27 Speaker 01 I understand.
2:28 Neil deGrasse Tyson? Where did it come from? And when this problem was discovered, this is now, you know, 80 years ago, it was called the missing mass problem. There's surely some mass out there, but we can't find it.
2:38 Speaker 01 Where is it?
2:38 Neil deGrasse Tyson? Because I see gravity from it.
2:40 Speaker 01 Mm-hmm.
2:41 Neil deGrasse Tyson? And so what's the solution? It is the longest standing unsolved problem in modern astrophysics, the dark matter problem. And so there are people who say, it's not a matter problem, you just don't understand gravity. Because why do I think there's too much gravity? Because I used an equation of gravity that told me that. An equation handed to me by Isaac Newton, his universal law of gravitation.
3:07 Speaker 01 Okay.
3:07 Neil deGrasse Tyson? So I got his equation, I plug it in and I put in the numbers, it says, the matter that's out there is not giving me as much gravity as I see. So MAND takes, it starts out with Newton's gravity because it knows that works for most cases, but these extreme cases in galaxies and galaxy clusters, there's an extra term there, there's an extra acceleration to account for the extra gravity brought to you by the matter that we've all known and loved. That's MAND, modified Newtonian gravity. And it has some interesting, successful applications, but it doesn't explain everything.
3:44 Speaker 01 No.
3:45 Neil deGrasse Tyson? For example, we need dark matter in the early universe to explain anything we know about the formation of everything in the cosmos. So this, so they're still duking it out. And if I were to vote, I would say MAND is on its way out.
3:58 Speaker 01 Really?
3:59 Neil deGrasse Tyson? Yeah, but it was there fighting for a while.
4:01 Speaker 01 Well, I mean, isn't, doesn't that, that's what science does. You come up with what's a plausible explanation at the time and you test and you test and see if it stands up and if it doesn't, you throw it out.
4:09 Neil deGrasse Tyson? There's nothing wrong with a wrong idea.
4:12 Speaker 01 Right.
4:12 Neil deGrasse Tyson? The time you put it in, if it helps you try to solve a problem. One of the greatest wrong ideas ever was the geocentric universe with the earth in the middle.
4:20 Speaker 01 I thought you were gonna say leg warmers.
4:22 Neil deGrasse Tyson? I used to have leg warmers.
4:24 Speaker 01 Oh, you better stop.
4:24 Neil deGrasse Tyson? I used to wear leg warmers.
4:25 Speaker 01 You little flash dancer.
4:26 Neil deGrasse Tyson? Well, I used to dance, so I, so it was, I wasn't just wearing them because it was like, you know.
4:31 Speaker 01 You were chilly? Wow.
4:34 Neil deGrasse Tyson? Yeah, I still have them too.
4:35 Speaker 01 You are such a renaissance.
4:36 Neil deGrasse Tyson? Put them on and I then I point my toe and raise my leg. Yeah, yeah.
4:39 Speaker 01 Wow, Renaissance man.
4:40 Neil deGrasse Tyson? Well, not anymore. That was just like long ago. But anyhow, what else you got?
4:44 Speaker 01 In a galaxy far, far away. I have no question.
4:47 Neil deGrasse Tyson? There's still people working on Mond.
4:49 Speaker 01 Okay, even though they they didn't get the memo, it's on the way out.
4:51 Neil deGrasse Tyson? And we still don't have dark matter completely understood. So until that happens, you know, there'll be people still fighting the good fight and that's that's science at its best. Yeah.
5:00 Speaker 01 Love it.
5:01 Neil deGrasse Tyson? All right.
5:01 Speaker 01 I have a question from Anil Virik.
5:04 Neil deGrasse Tyson? Mm hmm.
5:04 Speaker 01 And it's about lightning.
5:05 Neil deGrasse Tyson? Where are the these people? Do we know where they're from?
5:07 Speaker 01 You know, um, Anil did not say.
5:09 Neil deGrasse Tyson? Okay.
5:09 Speaker 01 Oh, wait. Um, no, didn't say. They just sent the email.
5:13 Neil deGrasse Tyson? Okay, just an email. All right.
5:14 Speaker 01 So, uh, right now they're from Gmail.
5:18 Neil deGrasse Tyson? What country is that?
5:19 Speaker 01 That's everywhere.
5:20 Neil deGrasse Tyson? Yeah.
5:21 Speaker 01 Gmail is dark matter.
5:22 Neil deGrasse Tyson? Mm hmm.
5:22 Speaker 01 Uh, now I heard lately that lasers have been used to try to direct lightning strikes, strikes. Uh, the laser is shot into the thunderhead clouds and the plasma flows the laser back. Is there a way to harness this energy and make lightning farms?
5:37 Neil deGrasse Tyson? Well, first of all, that's that's the first I've heard of this and I think it's amazing. And I can even explain how it works, even though I only just learned of it.
5:46 Speaker 01 Because you're that bad.
5:47 Neil deGrasse Tyson? No.
5:49 Speaker 01 Cue music.
5:51 Neil deGrasse Tyson? The idea, a theme, a theme.
5:53 Speaker 01 You do. You're like, you're the shaft of science. What you talk about?
5:58 Neil deGrasse Tyson? Do you know, I was listening to, uh, uh, uh, XM radio, uh, seventies on seven, you know, because they have the sixties on six and seventies on seven. And on came the theme to Shaft. And I hadn't heard that in a long time. Who's the bad motherfucker, sex machine to all the chicks? And this goes on and on. And then immediately after that song, they didn't miss a beat. They played John Denver's Thank God I'm a Country Boy. It was like, no.
6:22 Speaker 01 Hey, Mr. DJ, did you not take your meds today?
6:27 Neil deGrasse Tyson? Now, I happen to like both songs, but you don't play them. This is not a mixtape. We're gonna play "Thank God I'm a Country Boy" after Shaft.
6:35 Speaker 01 You could have hurt yourself on a dance floor with that.
6:37 Neil deGrasse Tyson? Man, okay, now, sorry, I distracted myself. Where were we?
6:41 Speaker 01 Lightning farm, sir.
6:42 Neil deGrasse Tyson? So, here's what happens. Lightning comes about because there's a difference in charge between a cloud and the ground beneath it.
6:51 Speaker 01 Yes.
6:51 Neil deGrasse Tyson? And charges don't like being separate from one another. All right? The molecules reach an excited state because they've lost their electrons.
6:59 Speaker 01 Mm-hmm.
7:00 Neil deGrasse Tyson? They don't like staying that way.
7:02 Speaker 01 Okay.
7:02 Neil deGrasse Tyson? And all electrons are sitting on the ground, and those electrons want to get back to the cloud. And so, so the cloud comes over, the electrons gather, and they're ready to rise up and reach the cloud again. Thus is born a lightning strike, which tells you that lightning goes from the ground to the cloud, not the cloud to the ground.
7:21 Speaker 01 Really?
7:22 Neil deGrasse Tyson? Now, so, if you take a laser that's very high power and you ionize gas at the atmosphere in one place versus another, you can build charges around where the cloud is and force a lightning bolt to go where you say so. Now, that's good.
7:41 Speaker 01 Yeah.
7:42 Neil deGrasse Tyson? Now, the person wants to know if we can make a lightning farm out of that? I say, why not? More Cosmic Queries when we return.
8:09 Neil deGrasse Tyson? We're back on StarTalk After Hours. Leanne, I shouldn't keep calling. It's Cosmic Queries.
8:16 Speaker 01 No, I like the After Dark.
8:17 Neil deGrasse Tyson? You like that?
8:18 Speaker 01 Yes, it's part of the show's DNA now.
8:19 Neil deGrasse Tyson? Oh, thank you.
8:20 Speaker 01 We keep it.
8:21 Neil deGrasse Tyson? How bioliterate of you.
8:23 Speaker 01 Well, you know what? Hanging out with the folks of your ilk.
8:25 Neil deGrasse Tyson? This, if you can't be... Bioliterate here, you know, where can that happen? You're reading me questions.
8:32 Speaker 01 Yes.
8:32 Neil deGrasse Tyson? Call from the internet and right before the break, there was a question about lightning farms.
8:37 Speaker 01 Yes.
8:37 Neil deGrasse Tyson? By creating spots where the lightning would strike using high powered lasers that would ionize the air. And it's a great idea. At first I learned of it was that question, but it sounds great.
8:46 Speaker 01 It does.
8:46 Neil deGrasse Tyson? You just have to watch out that your lasers aren't so powerful to ionize the air in places so that you can force a lightning discharge that you're using more energy than you get back from the lightning itself.
8:56 Speaker 01 Because then that would be inefficient.
8:57 Neil deGrasse Tyson? It would, then you're not making a light, you're not farming anything.
9:00 Speaker 01 Right now.
9:01 Neil deGrasse Tyson? You're getting less than what you started with. Now, it turns out the act of forming a raindrop in a cloud takes some charge out of the cloud and brings it to the ground.
9:10 Speaker 01 Okay.
9:11 Neil deGrasse Tyson? So you're relying on the sun, which evaporated the water in the first place to make the cloud, to then drop the water, bringing charges to the ground. You're relying on that in the first place. So if the lasers just to help it out, to direct the lightning where it would have struck anyway, but now you strike to, strike it to your spot, your sweet spot, then you got a good farm going.
9:33 Speaker 01 I'm sorry, my what?
9:34 Neil deGrasse Tyson? I just had to say, I had to just clarify all of that. Yeah. Oh, sorry.
9:38 Speaker 01 I, I need a moment. I think I need a cigarette. The man said my sweet spot. I didn't hear anything after that. I'm gone. I'm just gone. I'm gone.
9:48 Neil deGrasse Tyson? We gotta bring it back into the show.
9:49 Speaker 01 Okay.
9:50 Neil deGrasse Tyson? Actually, I, I, I think we have a caller, actually.
9:52 Speaker 01 Do we really?
9:53 Neil deGrasse Tyson? Yeah.
9:53 Speaker 01 I love it.
9:54 Neil deGrasse Tyson? Yeah. So some people actually don't use the internet to bring in their questions. They actually use this old fashioned technology called a telephone.
10:01 Speaker 01 You're gonna have to explain that one.
10:02 Neil deGrasse Tyson? Let's find out. Caller, are you there?
10:04 Speaker 02 Yes, I am.
10:05 Neil deGrasse Tyson? Hello, caller.
10:06 Speaker 02 How are you today?
10:07 Neil deGrasse Tyson? Okay, you know my name, but I don't know your name.
10:09 Speaker 02 Well, I'm not gonna tell you right away if that's okay.
10:12 Neil deGrasse Tyson? Oh, okay.
10:13 Speaker 02 I, I actually called in to see if you could figure out what my name is.
10:17 Neil deGrasse Tyson? Oh, okay. All right.
10:20 Speaker 02 My dad was a physicist, a lot like yourself. He did cosmology, black holes and all that stuff.
10:25 Neil deGrasse Tyson? Mm-hmm.
10:26 Speaker 02 And so my mother named the first child, so she said that he could name the second child, which is me.
10:31 Neil deGrasse Tyson? Uh-oh.
10:32 Speaker 02 Yeah.
10:33 Neil deGrasse Tyson? You're giving naming rights to the physicist in the family.
10:36 Speaker 02 That's right.
10:36 Neil deGrasse Tyson? These are the same people who named quarks, up, down, top, bottom, strange and charmed.
10:42 Speaker 02 Exactly.
10:42 Neil deGrasse Tyson? These are the same, same people who couldn't come, come up with a more inventive name for their super collider, but super, the, the superconducting super collider. It's like, you know.
10:53 Speaker 01 Which I saw on the Super Friends.
10:56 Neil deGrasse Tyson? If astrophoke had, I'd call it the super duper collider, right? The physicist, I don't know if the, so have you led a disturbed life because of this? What, what name did you end up with?
11:05 Speaker 02 Well, I'm gonna see if you can figure it out.
11:07 Neil deGrasse Tyson? Okay.
11:08 Speaker 02 I think he did a little better than that.
11:10 Neil deGrasse Tyson? Alright.
11:11 Speaker 02 Okay, so my name is Daco, D A C O.
11:16 Neil deGrasse Tyson? D A C O.
11:18 Speaker 02 What do you think that stands for?
11:20 Neil deGrasse Tyson? I have no idea. Dec- Deco.
11:24 Speaker 02 Deco, but think of each letter as
11:27 Neil deGrasse Tyson? Okay, D.
11:28 Speaker 02 representing something in an equation.
11:30 Neil deGrasse Tyson? Something that would come out of the brain of a physicist.
11:33 Speaker 02 Okay, give me a hint on the, on the D.
11:35 Neil deGrasse Tyson? Well, let me try, well, D could be like delta, perhaps. Or D could be, the little d as when you're taking a derivative in calculus. Oh, it is.
11:43 Speaker 02 That's, you got the D?
11:44 Neil deGrasse Tyson? Okay, so D A, alright, um, would be a derivative of the variable A. And A could be acceleration.
11:54 Speaker 02 That's it?
11:55 Neil deGrasse Tyson? Oh, it is! I'm loving it! Oh my god! It's like a movie. Okay. It's like a Dan Brown movie, you're figuring out the However, the, the first derivative of acceleration is hardly ever talked about because it, it, it's called the jerk. Did you know, did you know that? It's called the jerk. It's called the Steve Martin?
12:14 Neil deGrasse Tyson? So, if you, if you put on the brake in a car and then you start leaning forward, that's a constant lean. When, when a plane takes off on the runway, there's a constant pressure that you feel backwards. Alright, so under constant acceleration, you're leaning. Right. If you change the acceleration, you jerk. Yes. Okay? Okay. That's how you go. Got it. So, if you're slowing down constantly, but then you slam on the brake, you jerk forward rather than lean forward smoothly. Okay. So, the first derivative of acceleration will be the jerk, okay?
12:47 Speaker 02 Let me give you a little hint on the C. It has something to do with E equals M C squared.
12:52 Neil deGrasse Tyson? Well, C is, would clearly be the speed of light, but I don't know what D A would be, though, relative to C as the speed of light. And then I thought, O could be like a little O, so, uh, I don't know, the speed of light in a vacuum, perhaps? But I could, uh, but, uh, other than that, I have no idea where he was going with this.
13:11 Speaker 02 Well, I, I think you, you answered the question, because I think it's the speed of light.
13:18 Speaker 02 So, the way I understand it is that D is derivative, A is acceleration, C is a constant at an E equals M C squared,
13:26 Neil deGrasse Tyson? Yes.
13:27 Speaker 02 And O is zero. So, I'm thinking no change in acceleration at the speed of light and that just makes me the speed of light, but again, I'm not the physicist, I don't really know. I just have to go on faith here.
13:39 Neil deGrasse Tyson? What, well, he didn't tell you?
13:41 Speaker 02 Well, he said it was an equation.
13:44 Neil deGrasse Tyson? Oh, okay, I think we still could work on this.
13:47 Speaker 02 You think so?
13:48 Neil deGrasse Tyson? Let me keep work, let me think about this some more. I'll give you the speed of light, but the DA, I don't know, it's, let me think this one through.
13:56 Speaker 01 I love it, that is such a great first date conversation.
14:00 Speaker 02 I know, it's, it's always been a topic of conversation, really.
14:03 Speaker 01 That's so built in and wonderful.
14:05 Speaker 02 And just think, if I was a physicist, I would, you know, have a great name, but I'm not, I can't get my head wrapped around all that math.
14:13 Neil deGrasse Tyson? I'll hook you up.
14:14 Speaker 02 In fact, I'm a writer, and I actually just debuted with my first novel, it's a thriller, it's called The Libra Affair.
14:22 Neil deGrasse Tyson? The Libra Affair.
14:23 Speaker 02 Yeah, and actually, it's relevant to you, because the, um, the heroine is a NASA scientist.
14:28 Neil deGrasse Tyson? Uh huh.
14:29 Speaker 01 Love it.
14:30 Speaker 02 And the heroine targets him, she's a lady spy, because she wants to get a hold of his laser that's going up in space with SpaceX.
14:37 Neil deGrasse Tyson? The chicks dig the lasers.
14:38 Speaker 01 They like the laser.
14:39 Speaker 02 He's sending it up to zap space debris, which is really relevant today, and she wants to get a hold of it to zap a missile, but, yeah, it's quite interesting, huh?
14:49 Neil deGrasse Tyson? Wow, well, congratulations on that.
14:52 Speaker 01 Yes.
14:52 Speaker 02 Thank you, thank you, it came out and I'm, I'm really excited and, um, maybe I'll do well.
14:58 Neil deGrasse Tyson? Well, and, and you're surely the only Deco in, uh, in the world, so.
15:03 Speaker 02 That's right.
15:03 Neil deGrasse Tyson? One does, you could, you can start, you can start going solo name on this, who needs your last name when you have a unique first name?
15:10 Speaker 02 You know what, I'm publishing under only my first name, Deco. And my logo is thrillers at the speed of light.
15:18 Neil deGrasse Tyson? Oh.
15:19 Speaker 01 You are so on it. What's the name of your book, hon?
15:21 Speaker 02 The Libra Affair.
15:23 Speaker 01 The Libra Affair.
15:23 Neil deGrasse Tyson? The Libra Affair. Libra, of course, is a constellation, one of the twelve of the traditional zodiac.
15:28 Speaker 01 Traditional, because they did change last year.
15:29 Neil deGrasse Tyson? Well, no, we've had thirteen constellations forever in it.
15:32 Speaker 01 Oh, they just didn't mention it to other people?
15:34 Neil deGrasse Tyson? Every two years, people forget it, and someone announces it, and they think it's something new that got discovered.
15:39 Speaker 01 Wow.
15:39 Neil deGrasse Tyson? And, in fact, the symbol for pound in our world is what?
15:43 Speaker 01 Hashtag?
15:44 Neil deGrasse Tyson? No. Well, it can be that, but it's letters. It's what?
15:46 Speaker 01 L.B.
15:47 Neil deGrasse Tyson? L.B., which is Libra. Did you know that?
15:49 Speaker 01 Uh.
15:49 Neil deGrasse Tyson? Most people, like, write L.B. all their whole lives and don't know that means, uh, Libra.
15:55 Speaker 01 I had no idea.
15:55 Neil deGrasse Tyson? Yeah. You never stopped and thought, why does L.B. stand for pound?
15:59 Speaker 01 Uh, no, dude, I really didn't. I had other fish to fry.
16:02 Neil deGrasse Tyson? Libra is the scales. And Libra is the constellation in the sky that has the star names that are the longest of all the others.
16:09 Speaker 02 How about that?
16:10 Neil deGrasse Tyson? Yeah.
16:10 Speaker 01 You would be hella great on Jeopardy.
16:12 Neil deGrasse Tyson? No, no, so let me tell you. So, two of the stars in the constellation Libra, one is Zubel Janubi, and the other one is Zubel Shemali.
16:19 Speaker 02 Wow.
16:19 Speaker 01 Zubel Jalubi?
16:21 Neil deGrasse Tyson? Zubel Janubi and Zubel Shemali.
16:24 Speaker 01 Someone who listens to this show is naming their twins this as we speak. And it's your fault.
16:31 Neil deGrasse Tyson? So, did you, when you grew up, Deco, did you, like, were you beaten up by other girls who?
16:37 Speaker 02 Well, they didn't beat me up. They were afraid of me because I was so unique. I had this unique name.
16:42 Speaker 01 She's the speed of light. How could they catch her?
16:43 Neil deGrasse Tyson? There you go.
16:44 Speaker 02 They couldn't catch me.
16:45 Neil deGrasse Tyson? You got it. Well, I'm gonna keep working on your, on your thing. Now, did you have a question, or was your question, what was the meaning of your name?
16:51 Speaker 02 Well, I wanted to see if you could figure out what my name meant.
16:54 Neil deGrasse Tyson? Okay, I can, I think I can do better than just representing them as single symbols, because maybe they come together in some important way.
17:01 Speaker 02 Well, that would be interesting, because I've, you know, I've got on my website this meaning, and if I'm wrong, boy, I need to correct that.
17:08 Neil deGrasse Tyson? Let me see if I can.
17:08 Speaker 02 I've got the whole literary world believing that I'm the speed of light.
17:12 Neil deGrasse Tyson? No, we can still get the speed of light in there, because C is the speed of light. We're not gonna argue that.
17:16 Speaker 02 Okay.
17:17 Neil deGrasse Tyson? Let me work on it, and we'll get back to you.
17:19 Speaker 02 Okay, super. Thank you so much for taking my call. It's been so much fun.
17:23 Neil deGrasse Tyson? Happy to have you on. Well, thanks for calling StarTalk, the Cosmic Queries Edition. So, so Leanne.
17:31 Speaker 01 Yes.
17:32 Neil deGrasse Tyson? Yeah, so, so what was your mother smoking when she named you?
17:35 Speaker 01 Um, I had, listen, you ask what my dad was smoking, because this is what happens when you let fathers name their kids.
17:40 Neil deGrasse Tyson? Oh, is that what that is?
17:41 Speaker 01 Yes, my dad was a big fan of Vivian Leigh.
17:43 Neil deGrasse Tyson? Oh.
17:44 Speaker 01 That's how I got the L E I G H.
17:46 Neil deGrasse Tyson? Uh huh.
17:46 Speaker 01 And then they just threw, tacked on the end, so where people think I'm from the South, and I'm not.
17:51 Neil deGrasse Tyson? Yeah, Leanne, where's your accent? Yeah, but you're from Brooklyn or something, right?
17:54 Speaker 01 I'm from Queens.
17:56 Neil deGrasse Tyson? Queens, excuse me.
17:58 Speaker 01 Yeah, come on, get it right now.
17:59 Neil deGrasse Tyson? So I got like fifteen seconds, is there a fifteen second question there?
18:02 Speaker 01 No, man, there's really not. These, these people, these are emails, people did not feel constrained in any way.
18:07 Neil deGrasse Tyson? Huh.
18:08 Speaker 01 We have novel sized questions here.
18:10 Neil deGrasse Tyson? Oh, because if it came over Twitter, they, they'd contain it in a hundred and forty characters.
18:13 Speaker 01 Email, people are not containing themselves.
18:15 Neil deGrasse Tyson? All right, well, we'll get back to a longer question on the cosmos in the Cosmic Queries edition, right after this.
18:40 Neil deGrasse Tyson? We're back to the Cosmic Queries of StarTalk. I'm Neil deGrasse Tyson. Leanne.
18:46 Speaker 01 Leanne Lord is here.
18:48 Neil deGrasse Tyson? Leanne Lord, how are you?
18:49 Speaker 01 I'm excellent, how are you?
18:50 Neil deGrasse Tyson? All right, well, you were reading me questions before the break.
18:51 Speaker 01 I was.
18:52 Neil deGrasse Tyson? Called from, in this case, email, right?
18:54 Speaker 01 Yes.
18:55 Neil deGrasse Tyson? You know where they're from, sometimes they tell us where they're from?
18:56 Speaker 01 Well, actually, yes, I do have someone who has emailed us from Barcelona.
19:00 Neil deGrasse Tyson? Barcelona.
19:00 Speaker 01 Barcelona.
19:01 Neil deGrasse Tyson? Yeah.
19:02 Speaker 01 Yes, they have the lift.
19:03 Neil deGrasse Tyson? Yes.
19:04 Speaker 01 Uh, and this is from Joan.
19:05 Neil deGrasse Tyson? Beautiful, beautiful city, of course.
19:06 Speaker 01 Of course.
19:07 Neil deGrasse Tyson? Yeah.
19:07 Speaker 01 I wouldn't know.
19:09 Neil deGrasse Tyson? You gotta get out.
19:10 Speaker 01 I don't get out, well, no, I get out, I just haven't been there.
19:12 Neil deGrasse Tyson? Okay.
19:13 Speaker 01 Um, this is from Joan, Joan, uh, Jean Perre, or Jean Perre, I'm not sure. And, uh, she says, congratulations on this great show, and it makes, uh, my daily two-hour train trips to work a lot easier, so we're helping people on their commute.
19:26 Neil deGrasse Tyson? Wow, thank you.
19:29 Speaker 01 Uh, now she says that, uh, some time ago, Stephen Hawking said that in a contact, uh, with an advanced civilization, uh, it could turn very bad for us, uh, same as when Europeans went to America. So, can the potential risks of contacting an alien civilization, uh, somehow be evaluated? Um, I guess that according to the history of only advanced civilization that we know, uh, so far, it doesn't look pretty for us.
19:54 Neil deGrasse Tyson? Yeah, so all of our worries derive entirely from the fact that anytime we did that, we totally messed over the folks that we came upon.
20:04 Speaker 01 Just a bit.
20:04 Neil deGrasse Tyson? And the analogy here is that if anybody visits us, that means they cross the vast emptiness of space in some kind of vehicle that is beyond our capacity to accomplish.
20:19 Speaker 01 Right.
20:19 Neil deGrasse Tyson? Because we're not doing that.
20:20 Speaker 01 Right.
20:21 Neil deGrasse Tyson? Which would make them more advanced than we are.
20:23 Speaker 01 Mm-hmm. And coming over in Range Rovers is what they say.
20:27 Neil deGrasse Tyson? A, B, now they come over, in all the cases where the Europeans went to the New World, they had greater technologies than the people they came upon.
20:35 Speaker 01 Mm-hmm.
20:36 Neil deGrasse Tyson? And it's always been bad for the people with the lesser technologies. So the fear factor that Stephen Hawking is expressing is more a fear of how he knows we would treat other people than it is from any actual knowledge of how an actual alien would treat us. So in fact, he's holding up a mirror to our own cultures and our own motivations.
20:58 Speaker 01 So it's transference. We're assuming they're going to act like we.
21:01 Neil deGrasse Tyson? I didn't know there's such a word. Sure, the psychology talk, transference?
21:04 Speaker 01 Just a little bit.
21:05 Neil deGrasse Tyson? Yeah, transference. I'll go with that. That's what it was.
21:09 Speaker 01 I co-host a psychology show, so I learned some stuff over there and bring it here.
21:14 Neil deGrasse Tyson? All right.
21:15 Speaker 01 Okay.
21:15 Neil deGrasse Tyson? Next one.
21:16 Speaker 01 Our next question is from Emery. I hope I'm saying your name correctly. And she says, Dr. Tyson's explanation of how we could move.
21:24 Neil deGrasse Tyson? How do you know it's a she?
21:25 Speaker 01 I don't.
21:26 Neil deGrasse Tyson? You're assuming it.
21:26 Speaker 01 I am.
21:27 Neil deGrasse Tyson? Just to make that clear. Go on.
21:28 Speaker 01 Okay. So it wants to know.
21:29 Neil deGrasse Tyson? Yeah. It's okay.
21:33 Speaker 01 Dr. Tyson's explanation of how we could move incoming meteorites by parking a satellite next to it, lock them by gravity, then slowly tug them out of its trajectory got me to ask, what would it take to do something similar to planets? Like, could we move some of the planets to the Goldilocks zone? Would it mess up the orbits of Earth or Mars?
21:56 Neil deGrasse Tyson? Excellent question. So that would be sort of planetary engineering.
22:00 Speaker 01 Yes.
22:01 Neil deGrasse Tyson? Right. Oh, there's a planet we want to live on. If it's too close, or it's too far away, let's move it to the Goldilocks zone, where the temperature from the sun is just right for liquid water, as opposed to frozen water or evaporated water. We have words for those: ice and steam, right, or vapor.
22:17 Speaker 01 Wait, let me write that down. I learned so much here. Ice, how do you spell that?
22:21 Neil deGrasse Tyson? So, so if the day that we can start shifting planetary bodies around, like asteroids and then large asteroids, start small, work big. I don't see any reason why we can't just shifting, start shifting planets around. You have to be careful, because if planets get too close to one another, they create what are called resonances. And when you have a resonance, it means one planet does not orbit freely, it's locked in place relative to another planet. And when that happens, or their orbital periods are locked relative to one another. And so there are these weird gravitational sort of resonances out there that you want to watch out for, because some of them are unstable, and you can be flung out of the solar system entirely. In fact, the early solar system, we've hypothesized,
23:06 Neil deGrasse Tyson? justifiably, that we might have had 20, 30, 50 planets to start out in our solar system.
23:12 Speaker 01 Okay.
23:13 Neil deGrasse Tyson? Because you know what happens? If you create a solar system on a computer, and give it 50 planets, and let it just fight it out, you get like, a few planets left after a billion years or so. And the rest are cast into interstellar space. And they're called, they're called rogue planets. And in fact, there may be more rogue planets, homeless planets in the galaxy than planets that actually orbit actual stars.
23:38 Speaker 01 Homeless planets?
23:39 Neil deGrasse Tyson? Homeless planets. And so, yeah, I mean, nature does a lot of moving planets around. There are solar systems, star systems, where Jupiter's are close to the host star. Our Jupiter's far away, and we got Mercury, Venus, Earth, and Mars.
23:51 Speaker 01 Mm-hmm.
23:52 Neil deGrasse Tyson? Uh, between Jupiter and our sun. The other solar system where their Jupiter-sized object is really close. We think that Jupiter migrated inward, flinging other planets out.
24:03 Speaker 01 Out of my way. I need to be near the star.
24:05 Neil deGrasse Tyson? Exactly.
24:05 Speaker 01 It's a diva planet.
24:06 Neil deGrasse Tyson? Exactly. Well, that's what we should call them, diva planets.
24:09 Speaker 01 Diva planets. You heard it here first.
24:11 Neil deGrasse Tyson? We'll start it here first on StarTalk. Cosmic Queries. We've got time for one more question in this segment. What do you got?
24:17 Speaker 01 Uh, we know what? This is sort of comes off of, from the same person, off of the same theory. Um, could we move Mercury and Venus and how long would it take to cool them down sufficiently to terraform?
24:27 Neil deGrasse Tyson? Oh, uh, things cool off pretty quickly.
24:30 Speaker 01 Oh.
24:30 Neil deGrasse Tyson? Venus is nine hundred.
24:31 Speaker 01 Like a relationship.
24:32 Neil deGrasse Tyson? Not, Venus is hot enough to like melt lead and zinc and I calculated it would cook nine seconds, take nine seconds to cook a pizza on your windowsill. But then a geekier person than I am corrected me and said, no, you left out the radiative effects of the atmospheric, uh, uh, the thermal and so it actually would take a fraction of a second to cook. We gotta, when we come back, more on cooking pizza on Venus. Cosmic Queries after hour.
25:17 Neil deGrasse Tyson? We're back on StarTalk Radio. I'm Neil deGrasse Tyson. Leanne Lord is with me.
25:21 Speaker 01 Yes, I am.
25:22 Neil deGrasse Tyson? Co-hosting.
25:23 Speaker 01 Co-hosting. My favorite job.
25:24 Neil deGrasse Tyson? Comedian. That's my, were your favorite? You say that all your gigs.
25:27 Speaker 01 No, that's not true. I love you guys. You know, because we have the best fans. They tweet me so much. It's fantastic.
25:33 Neil deGrasse Tyson? Excellent. Excellent. Cause you're, you're on, in your stream.
25:35 Speaker 01 Yes.
25:36 Neil deGrasse Tyson? Yeah, good. So we left off talking about, uh, great question.
25:39 Speaker 01 Cooking pizza.
25:40 Neil deGrasse Tyson? Uh, move Mercury and Venus, I presume farther away to make them habitable.
25:45 Speaker 01 Right, to terraform.
25:45 Neil deGrasse Tyson? And they know Venus is very hot, Mercury is very hot. Bring them farther away from the sun, so the sun's rays are less intense.
25:52 Speaker 01 Mm-hmm.
25:53 Neil deGrasse Tyson? And bring them into the Goldilocks zone. Here's a problem with Venus. Venus is hot only in part because it's near the sun. It's especially hot because it has a runaway greenhouse effect. You, there's something about the carbon dioxide you're gonna have to fix before you want to live on Venus.
26:09 Speaker 01 So it's a fixer-upper planet?
26:10 Neil deGrasse Tyson? It's a total fixer-upper planet. Uh, CO2 is, it's 98% of the atmosphere and it's very dense, 100 times the atmospheric pressure on Venus as it is here on Earth. I guess it's probably closer to 90, but I rounded. To a hundred.
26:24 Speaker 01 Back of the envelope equation.
26:25 Neil deGrasse Tyson? Back of the envelope, yeah. Just round it just because what the difference between ninety and hundred is not important for the point I'm making. So I just round it to a hundred. And so it's about a hundred times the the atmospheric pressure that we have here on Earth. So you step out on Venus, you'll be crushed and vaporized simultaneously.
26:44 Speaker 01 But I'll look good because I'll be a lot slimmer for like a half a second.
26:49 Neil deGrasse Tyson? So you need to not only fix the CO2 problem, which is a greenhouse gas, as we all know. But also when you do that and then you let the planet cool down, that shouldn't take too long. Because it'll just radiate out into space. Look how fast Earth cools on a hot day after sunset in the desert.
27:08 Speaker 01 Okay.
27:08 Neil deGrasse Tyson? If you go to the desert, right? If it's dry, because actually moisture is a greenhouse gas itself. That's why in wet places you don't get high temperature extremes, but in deserts you do. It warms up in the daytime.
27:23 Speaker 01 Right.
27:23 Neil deGrasse Tyson? There's nothing to trap the heat. There's certainly no carbon dioxide and no water vapor. The heat escapes rapidly. Temperature dropped twenty, thirty degrees within a few hours.
27:32 Speaker 01 You know what? I always wondered that.
27:33 Neil deGrasse Tyson? That's why the deserts have huge temperature extremes and other place Hawaii does not.
27:38 Speaker 01 Okay.
27:39 Neil deGrasse Tyson? Completely surrounded by water.
27:40 Speaker 01 Now, is that because that the then the really hottest part of the day is really the end of the day? Because you still have that heat being released.
27:46 Neil deGrasse Tyson? The hottest part of the day is hottest part of the day is when the sun's rays are its most intense.
27:50 Speaker 01 Mm hmm.
27:51 Neil deGrasse Tyson? Well, that would be high noon. However, there's a time delay. That's when the sun's rays are most intense hitting Earth.
27:58 Speaker 01 Right.
27:59 Neil deGrasse Tyson? But the sun does not heat the air. The sun heats the ground, the ground heats the air. So there's a.
28:05 Speaker 01 Okay.
28:05 Neil deGrasse Tyson? And so there's a time delay between that that takes one or two hours. That's why the hottest time of day is two or three in the afternoon.
28:13 Speaker 01 Ah, that's what I was thinking of, okay.
28:15 Neil deGrasse Tyson? Your most susceptible to like sunburn is at high noon when the sun is has its most direct rays on you. So that's this time delay. And that's why the hottest month of the year is not June.
28:28 Speaker 01 No.
28:28 Neil deGrasse Tyson? Even though the sun is at its highest at any location on Earth, it's at its highest in that month. It takes a couple of months for the heat to hit the Earth and build up back and then warm the atmosphere. So visible light hits Earth, heats it. Earth re-radiates that same energy as infrared and it's the infrared that gets trapped by the greenhouse gases. If greenhouse trapped visible light, the visible light would never reach Earth's surface. It would trap it in midair.
28:56 Speaker 01 Oh.
28:56 Neil deGrasse Tyson? This is why we receive energy from the sun and then keep it with the greenhouse effect. Because most of the energy that we that becomes the greenhouse started out as visible light. It's very cool.
29:08 Speaker 01 You're good.
29:08 Neil deGrasse Tyson? That's right. No, no, it's the universe that's good.
29:11 Speaker 01 Well, no, I mean, the way you explain it, though.
29:14 Neil deGrasse Tyson? Good.
29:15 Speaker 01 No, no, you're fantastic.
29:17 Neil deGrasse Tyson? Yeah, so stuff cools pretty quickly. That's not the problem. Yeah. What else you got?
29:21 Speaker 01 All right, I have a question. I don't have a name. This person is shy.
29:26 Neil deGrasse Tyson? An anonymous email.
29:27 Speaker 01 Well, I can say this, they're from a school because it's a .edu. So it's a student.
29:31 Neil deGrasse Tyson? Institution.
29:32 Speaker 01 Yes, I'm just putting on my CSI cap here. And they want to know who was our most scientifically friendly president? Like, which one of our US presidents was the most friendly to the field of science?
29:42 Neil deGrasse Tyson? Ever?
29:43 Speaker 01 Ever.
29:44 Neil deGrasse Tyson? Yeah, it depends on what you mean by friendly. In Washington, friendly means how much money do you give the enterprise? That's what that's what in Washington, all that matters is money. What you say doesn't matter at all.
29:54 Speaker 01 Okay.
29:55 Neil deGrasse Tyson? Okay.
29:55 Speaker 01 But then let's go.
29:56 Neil deGrasse Tyson? Just an FYI.
29:57 Speaker 01 Got you.
29:58 Neil deGrasse Tyson? Okay, all right. So a few things. Abe Lincoln began the National Academy of Sciences. Now, that's kind of cool.
30:09 Speaker 01 Very.
30:09 Neil deGrasse Tyson? It was set up to establish an advisory board to Congress that was not itself politically motivated for any reason. And so Congress would call on the National Academy of Sciences to produce studies on scientific issues that befall the day. I got to put Lincoln at the top of that list.
30:29 Speaker 01 Okay.
30:29 Neil deGrasse Tyson? As the most scientifically aware and literate.
30:32 Speaker 01 So he was not just a cat owner?
30:34 Neil deGrasse Tyson? I didn't know he owned cats.
30:35 Speaker 01 He was the first president to have a cat?
30:37 Neil deGrasse Tyson? I did not. Why do you even know that?
30:39 Speaker 01 Because I was getting tired of the slavery thing. Like, what else did he do?
30:42 Neil deGrasse Tyson? When we come back, more of Cosmic Queries on StarTalk.
31:04 Neil deGrasse Tyson? StarTalk, Cosmic Queries, Leanne Lord with me here in studio.
31:09 Speaker 01 You didn't say my favorite line.
31:11 Neil deGrasse Tyson? What is that?
31:11 Speaker 01 StarTalk, Cosmic Queries after dark.
31:13 Neil deGrasse Tyson? It exists in the dark. So, we left off talking about Lincoln. The question was, who's the most science-friendly president?
31:20 Speaker 01 Yes.
31:20 Neil deGrasse Tyson? And I'd have to say, given all the things that presidents have done, you know, Jefferson was quite scientifically literate. President Obama has mentioned science in practically every speech he's given.
31:30 Speaker 01 Mentioned.
31:31 Neil deGrasse Tyson? I know.
31:31 Speaker 01 I like the way, that's very political of you.
31:33 Neil deGrasse Tyson? I'm still waiting for the money on that.
31:35 Speaker 01 Show me the money.
31:36 Neil deGrasse Tyson? And Republicans, in the second half of the 20th century, tended to give more money to science, because science was viewed as an engine of our national security. So it wasn't so much that they were curious about the frontier, but just that science was good for war, essentially, and for winning wars. But Lincoln, there's another bit about Lincoln. You read the Gettysburg Address?
31:58 Speaker 01 Um, I read Abraham Lincoln.
31:59 Neil deGrasse Tyson? Don't say "um," don't start that with an "um."
32:00 Speaker 01 I read Abraham Lincoln Vampire Hunter.
32:02 Neil deGrasse Tyson? Okay.
32:03 Speaker 01 I think they covered it.
32:04 Neil deGrasse Tyson? A Gettysburg Address, I don't memorize the whole thing, but fourscore and seven years ago, "Our four fathers brought forth a new nation, conceived in liberty," it goes on like that. If you feel the rhythm of it, it's five, six, seven words at a time.
32:16 Speaker 01 Mm-hmm.
32:17 Neil deGrasse Tyson? And that's like the right number of words for an attention span if you're listening to someone speak. Think about that.
32:25 Speaker 01 Okay.
32:26 Neil deGrasse Tyson? Yeah. And then I thought about it, and I said, why is this speech so effective? Of all the speeches given by all the politicians, this one is up on the wall, and there are no complex sentences within it. If you take a quill pen and dip it, you have about as much ink as will get you five, six, seven words.
32:47 Speaker 01 Yeah.
32:48 Neil deGrasse Tyson? And it occurred to me that feather pen writing of speeches forces a rhythm in your communication that is the perfect marriage of words on a page and words to the ear. So to this day, when I'm preparing an important speech... I will write that speech with a quill pen.
33:07 Speaker 01 No.
33:08 Neil deGrasse Tyson? Or I will dip my fountain pen unfilled. The fountain pens can store ink.
33:13 Speaker 01 Yes.
33:14 Neil deGrasse Tyson? That doesn't count. It's unlimited ink until you run out. I will not fill it and I will dip it in a well and I will write it out that way. And it forces me to contain the ideas in morsels, in parcels of information, which then is my hope that the listener will embrace.
33:30 Speaker 01 Love it.
33:31 Neil deGrasse Tyson? And so I have a collection of fountain pens and quill pens.
33:34 Speaker 01 I do too.
33:34 Neil deGrasse Tyson? I just go there.
33:35 Speaker 01 I'm a pen person.
33:36 Neil deGrasse Tyson? Just what I do.
33:36 Speaker 01 We've talked about this.
33:37 Neil deGrasse Tyson? And sometimes I go all the way if I'm writing with a quill pen. I like candles because that's how.
33:42 Speaker 01 Well, that's how it should be done.
33:43 Neil deGrasse Tyson? That's how, if you're gonna go there.
33:44 Speaker 01 Do you put on the powdered wig? I need a picture of you in the powdered wig. This is fantastic.
33:49 Neil deGrasse Tyson? No, I don't do wig.
33:50 Speaker 01 Nothing yet. Come on now. You're not doing it the whole way. Ah, come on.
33:54 Neil deGrasse Tyson? So now we're going on to Cosmic Query's lightning round.
33:57 Speaker 01 Lightning round.
33:58 Neil deGrasse Tyson? Let me get the bell. Test it. There we go. All right, let's do this, Leanne.
34:04 Speaker 01 Lightning round, my favorite. All right. This is from Mike Hall. And he wants to know, are there valuable resources that are easier to obtain from space than drilling into the earth for?
34:13 Neil deGrasse Tyson? Ah, they're not easier to get to, but oh, so you want them.
34:18 Speaker 01 Ooh.
34:18 Neil deGrasse Tyson? Because on earth, we fight wars over resources that are underfoot.
34:22 Speaker 01 We do.
34:22 Neil deGrasse Tyson? And the universe is an unlimited supply of all the resources that we fight each other to get down here on earth. So whether or not they're easier to get, they're better to get. Next.
34:31 Speaker 01 Got it. All right. Next question is from Chris Van Gundy. Uh, how can we determine the difference between a brown dwarf and a large rogue planet?
34:39 Neil deGrasse Tyson? Oh, it's hard. Uh, brown dwarf is a star that didn't make it and a large rogue planet is just a big old chubby planet. There are astrophysical differences between the two, but they're very hard to notice from a distance. So it's very hard. It's one of the big challenges. And we got low mass star people and high mass planet people meeting in the dark of night trying to solve that problem.
35:00 Speaker 01 You said chubby planet. Next question is from Peter O'Hara, and he says, can you give us your take on parallel universes? They sound really cool.
35:08 Neil deGrasse Tyson? I agree, parallel universes are awesome, but you should think of them not as parallel to one another, but as the consequence of the multiverse. In the multiverse, you have multiple universes popping out of some original distortion of the fabric of space and time. We are just one of multiple universes, hence the multiverse. And so there could be other universes adjacent to us in a higher dimension, and we would never know it. I think of them as parallel universes. Next.
35:35 Speaker 01 Nice. Joshua Jenkins wants to know, why does the Earth spin in the direction it does? And what if Earth started spinning twice as fast as it does now?
35:43 Neil deGrasse Tyson? Ooh, okay, so we spin this direction because, I'm gonna say it exactly physically, you ready?
35:48 Speaker 01 Yes.
35:48 Neil deGrasse Tyson? That is the direction of the angular momentum of the entire solar system.
35:52 Speaker 01 So we're going with the flow?
35:54 Neil deGrasse Tyson? Beautiful. We're going with the flow. The sun spins that way. All planets orbit that way. The moons orbit that way. Everybody is going counterclockwise as viewed from the top. Now, why do they want to spin up Earth? I don't know. That would have the length of the day. There would be 12-hour days instead of 24-hour days.
36:13 Speaker 01 Oh, I can't get enough done.
36:14 Neil deGrasse Tyson? And the act of spinning us up, okay, we'll feel that. That would not be a good day on Earth. Okay. You will know when Earth starts spinning faster. Well, you know what'll happen? Stuff behind you will run into you, and you'll be flattened against it, and you'll be a pile of goo on the wall behind you. Because you're, right now, you're moving 800 miles an hour with the rotation of the Earth. If you all of a sudden start going 1,600 miles an hour, something came in behind you to push you to do that, and that will flatten you into a pile of goo. Next.
36:41 Speaker 01 Yeah, not with it.
36:42 Neil deGrasse Tyson? Fast.
36:43 Speaker 01 Ray Day, what would your opinion be on the seemingly regularity of mass extinctions on Earth?
36:48 Neil deGrasse Tyson? They're not really regular. There's some analysis where you can see, oh, every 20 million years, things go extinct. But you have to cut the data in a way that makes it look that way. If you don't cut the data, the regularity is not really there.
37:01 Speaker 01 Okay.
37:01 Neil deGrasse Tyson? So extinctions happen kind of randomly, and we're in the middle of what's called the sixth great extinction on Earth, and that extinction is caused by humans. We gotta run. Oh. Gotta go. That's it. Wow. StarTalk, brought to you in part by the National Science Foundation, Leanne Lord, Great Avenue. Thank you. I'm Neil deGrasse Tyson, as always, keep looking tough.
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