Pod Insights StarTalk Podcast Cosmic Queries: Dark Mysteries of the Universe About this episode Join Neil deGrasse Tyson and comic co-host Leighann Lord as they explore the dark mysteries of our cosmos, from black holes and neutron stars to dark flow and the Higgs field.
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, astrophysicist Neil deGrasse Tyson, and this is Cosmic Queries.
0:31 Neil deGrasse Tyson? Keep thinking of it as an after-hours kind of thing.
0:33 Speaker 01 It has that feel to it.
0:34 Neil deGrasse Tyson? That is the voice of Leanne Lord. Leanne, thanks for being on StarTalk again.
0:38 Speaker 01 Thank you for having me back. You know I love it here.
0:40 Neil deGrasse Tyson? Oh, excellent, because plus you're a geek person.
0:43 Speaker 01 Totally.
0:43 Neil deGrasse Tyson? Totally geek, so you can do this. And in our Cosmic Queries additions, we get one of our favorite comedians, in this case it's you.
0:50 Speaker 01 Thank you.
0:51 Neil deGrasse Tyson? To call the internet on our websites and all our social media to collect questions, sometimes solicited, others, the questions just come in.
0:58 Speaker 01 They do.
0:58 Neil deGrasse Tyson? Because people are bubbling with curiosity.
1:00 Speaker 01 Right, and you know, to have a personal astrophysicist.
1:03 Neil deGrasse Tyson? Yeah, I'd like to.
1:03 Speaker 01 Why would you not take advantage of that?
1:05 Neil deGrasse Tyson? Sure, so, let's go ahead and do that. I haven't seen these questions before, and not to stump me or anything, but just, my answers are fresh, and if I don't know something, I'll tell you.
1:14 Speaker 01 Okay.
1:15 Neil deGrasse Tyson? Go for it.
1:15 Speaker 01 Alrighty.
1:16 Neil deGrasse Tyson? The topic is dark things, right?
1:18 Speaker 01 Yeah, we're exploring the dark mysteries of the universe here.
1:21 Neil deGrasse Tyson? Mystery, mysteries or dark mysteries?
1:23 Speaker 01 Dark mysteries.
1:24 Neil deGrasse Tyson? Okay.
1:25 Speaker 01 With quotes?
1:27 Neil deGrasse Tyson? Dark mysteries, let's go for it.
1:28 Speaker 01 Alright, well, this first question, we're coming in from Nick Fisher, and he wants to know, if all this light is created in the universe and travels for billions of years, why is it still so dark?
1:40 Neil deGrasse Tyson? Ooh.
1:41 Speaker 01 Yeah.
1:42 Neil deGrasse Tyson? Ooh.
1:43 Speaker 01 Good question.
1:44 Neil deGrasse Tyson? Well, a couple of things. There's light from stars that comes for billions of years across the universe, and when you look at that light, you see the star. So, it's not dark.
1:56 Speaker 01 Right.
1:56 Neil deGrasse Tyson? It's dimmer, but it's not dark. And light comes from the billions of stars of galaxies. The billions of stars contained within a galaxy, you look to the edge of the universe, there's a galaxy there. So, it's not dark. So, galaxies and stars and things, they are themselves not dark, alright? So, they get dimmer, but they're not dark. Now, how about the rest of what is dark?
2:18 Speaker 01 Yes.
2:19 Neil deGrasse Tyson? It's not dark.
2:20 Speaker 01 It's not.
2:20 Neil deGrasse Tyson? It is ablaze in microwave light.
2:24 Speaker 01 Does that mean it's blazing, but we can't see it?
2:26 Neil deGrasse Tyson? Uh, your eyes can't see microwaves.
2:28 Speaker 01 Oh.
2:29 Neil deGrasse Tyson? Yeah, if, if your eyes could see-
2:30 Speaker 01 No matter what prescription I put in.
2:32 Neil deGrasse Tyson? Exactly right. So, the whole spectrum of light is not just Roy G. Biv, which is-
2:38 Speaker 01 Um, Roy G. Biv, the colors, red, orange, yellow, green, blue, indigo, violet.
2:43 Neil deGrasse Tyson? Excellent.
2:44 Speaker 01 That's my closet.
2:44 Neil deGrasse Tyson? Indigo is the tricky one that people never get. So-
2:47 Speaker 01 Who doesn't get indigo?
2:47 Neil deGrasse Tyson? Uh, Isaac, Isaac Newton first net labeled those colors, and that's the, that's visible light. And for the longest time, we thought that that was the only way that light could exist. And if we're looking out in the universe, that's the only way that the universe would speak to us. Until we learned that below red, we have infrared, and above violet, we have ultraviolet.
3:09 Speaker 01 Oh.
3:10 Neil deGrasse Tyson? And beyond that, and, and, and the light goes in each direction. So, your eyes are not the measure of all that can be seen in the universe. And the methods and tools of the astrophysicist, over the past century, we have found ways to detect light far outside of visible light.
3:26 Speaker 01 Right.
3:26 Neil deGrasse Tyson? And that includes radio waves, and gamma rays, and X-rays, and, and microwaves. And the universe is ablaze in microwave light.
3:34 Speaker 01 Wow, we just can't see it with the eyes we have.
3:36 Neil deGrasse Tyson? If you were Geordi.
3:38 Speaker 01 Geordi La Forge with the banana clip visor.
3:40 Neil deGrasse Tyson? That visor enables him on Star Trek: Next Generation-
3:44 Speaker 01 Next Gen, of course.
3:45 Neil deGrasse Tyson? To see all the spectrum of light that even the human eye can't see. And he would look up, tune in, and say, "The universe is a glow."
3:53 Speaker 01 You know, that actually brings up an issue. He possibly unfairly then got his job because he can see stuff that other people, uh, could not.
3:59 Neil deGrasse Tyson? Uh, you mean Geordi on, on the-
4:01 Speaker 01 Yes, on the show, not the actor.
4:06 Neil deGrasse Tyson? The actor Kunta Kinte, the actor.
4:07 Speaker 01 The actor Kunta Kinte.
4:09 Neil deGrasse Tyson? Yeah.
4:09 Speaker 01 Did you seriously go back to roots?
4:11 Neil deGrasse Tyson? I so did.
4:12 Speaker 01 Let's throw a little reading rainbow in there. We'll just give his whole resume, why don't we?
4:16 Neil deGrasse Tyson? We met, we have a StarTalk episode.
4:18 Speaker 01 Yeah, I know.
4:19 Neil deGrasse Tyson? I bumped into them. I mean, we, we arranged an interview at Comic-Con 2012.
4:24 Speaker 01 Brent Spiner, yes.
4:24 Neil deGrasse Tyson? And Brent Spiner was there too, uh, Data.
4:27 Speaker 01 So jealous.
4:27 Neil deGrasse Tyson? Yeah, we told together, we had them together. It was like the-
4:30 Speaker 01 That's one of my favorite photos.
4:31 Neil deGrasse Tyson? The space-time continuum almost imploded there. So, uh, so what else you got?
4:36 Speaker 01 All right, I have a question from Joe Vera.
4:37 Neil deGrasse Tyson? Mm-hmm.
4:38 Speaker 01 And, uh, he says, "I recently found out about something called dark flow." Isn't that a DJ?
4:44 Neil deGrasse Tyson? Dark flow.
4:45 Speaker 01 Okay, I'm sorry. Yeah, exactly.
4:47 Neil deGrasse Tyson? A beatboxing DJ, dark flow. That's a great name.
4:51 Speaker 01 It is, isn't it? Something like a cartoon. All right, um, now, from what I gather, it is the un-
4:55 Neil deGrasse Tyson? The other great name for it was like MC squared, that's it, you know, if you want to be MC.
4:59 Speaker 01 I'm gonna pretend I didn't hear that. Be there or be a four-sided polygon. Can we get any geekier? All right.
5:06 Neil deGrasse Tyson? Gotcha, go on.
5:07 Speaker 01 All right, from what I gather-
5:08 Neil deGrasse Tyson? But four-sided polygons are not always square. They could be-
5:11 Speaker 01 Arambus?
5:12 Neil deGrasse Tyson? Rumbus, yeah.
5:12 Speaker 01 Which is my favorite. Love arambus. We're never getting to this question.
5:17 Neil deGrasse Tyson? I know, go, sorry.
5:17 Speaker 01 Okay, all right, so, "Recently found out about something called dark flow."
5:20 Neil deGrasse Tyson? On this show, you're allowed to get your geek on. If you can't do that here-
5:23 Speaker 01 If you can't geek out here.
5:24 Neil deGrasse Tyson? Where?
5:24 Speaker 01 Exactly.
5:25 Neil deGrasse Tyson? All right, go on.
5:26 Speaker 01 All right, "From what I gather, it is the unexplained coherent motion of galaxies toward one side of the universe. Can you please elaborate on this phenomenon and is it po- and its possible ramifications for our understanding of the universe?"
5:38 Neil deGrasse Tyson? Yeah, there's something called the Great Attractor. It got labeled that because when you-
5:42 Speaker 01 I know that guy.
5:44 Neil deGrasse Tyson? When you, uh, measure the speed of galaxies as they move in the universe, there are multiple ways to do this. One of them is just how fast is the universe expanding? So that's the speed they have just from the expanding universe. But while that's happening, galaxies are moving among themselves. For example, we are about to, in seven billion years or so, about to collide-
6:02 Speaker 01 We better hurry.
6:03 Neil deGrasse Tyson? With the Andromeda Galaxy. It's our nearest big galaxy. So we're about to collide, but the greater activity of the universe is expansion while galaxies are still moving among themselves.
6:14 Speaker 01 Okay.
6:15 Neil deGrasse Tyson? So, when you map the speeds of all these galaxies, it was found that there's a whole swath of galaxies in the universe that have sort of an extra motion towards one direction. So you don't know if they're escaping something or being drawn towards something.
6:30 Speaker 01 Run, everybody!
6:31 Neil deGrasse Tyson? So, it's an, it's an interesting sort of phenomenon that's not completely explained.
6:36 Speaker 01 So you just didn't explain it?
6:38 Neil deGrasse Tyson? That's true.
6:39 Speaker 01 I love it. You made it sound real good, though. That's nice. Wow.
6:42 Neil deGrasse Tyson? If somebody figured it out recently, I haven't read about it, but put it that way.
6:45 Speaker 01 Well, check your Twitter stream.
6:46 Neil deGrasse Tyson? I'll check, I'll check it, yes.
6:48 Speaker 01 All right. That's hilarious. All right, next question is from John Coleman. And he says, "Is there any possibility that the singularity that created our universe is still active and part of the reason the universe is expanding?"
6:59 Neil deGrasse Tyson? Oh, no, the singularity was a point in space and time.
7:03 Speaker 01 Oh.
7:04 Neil deGrasse Tyson? It is not still around. We, we are the singularity writ large across the dimensions of the cosmos.
7:11 Speaker 01 I'm gonna put that on a t-shirt. I'm a singularity. What are you?
7:14 Neil deGrasse Tyson? No, you were once a singularity.
7:15 Speaker 01 I was once a singularity.
7:16 Neil deGrasse Tyson? We are what the singularity became.
7:18 Speaker 01 I'm a has-been.
7:19 Neil deGrasse Tyson? So, is it, is it good for you?
7:21 Speaker 01 It's good for me.
7:22 Neil deGrasse Tyson? Okay. We have like, like 15 seconds left. See what you can give me in 15 seconds.
7:28 Speaker 01 All right. Kevin Pulito wants to know, according to the theory of the multiverse, what is space, he'll call it space, between universes?
7:35 Neil deGrasse Tyson? No, 15 seconds is not enough time to answer that question. So, when we come back on StarTalk Radio, the Cosmic Queries Edition, more of the questions, your questions, called from the internet, from our Facebook page, like us on Facebook. And of course, you can put your questions online at starTalkRadio.net. We will be right back.
8:36 Neil deGrasse Tyson? This is StarTalk, the Cosmic Queries Edition, which I like to think of as StarTalk after hours. Leanne Lord, thanks for being with me.
8:44 Speaker 01 Oh, always. Thank you.
8:45 Neil deGrasse Tyson? And you tweet at Leanne Lord.
8:47 Speaker 01 I do.
8:48 Neil deGrasse Tyson? But you spell your name funny.
8:49 Speaker 01 I do. My parents spelled my name funny.
8:51 Neil deGrasse Tyson? You could change it. L-E-I-G-H-A-N-N, Leanne Lord. That's your Twitter handle. And I know where you're, where you're performing, because I, I'm on your list at veryfunnylady.com.
9:02 Speaker 01 Yes, you can spell that. That's easy.
9:06 Neil deGrasse Tyson? So you've got questions that you're
9:07 Speaker 01 I do.
9:08 Neil deGrasse Tyson? I haven't seen these questions before and they're all, they're all that is mysterious and dark in the universe.
9:13 Speaker 01 Yes, yes.
9:14 Neil deGrasse Tyson? Now, we left off, there was one, read me that question again.
9:16 Speaker 01 Yeah, yeah, yeah, because I thought it was a good question. And this is from Kevin Polito again, and he said, according to the theory of multiverse, what is, what is space, and he says, I'll call it space, between universes? What is the space between universes?
9:28 Neil deGrasse Tyson? Yeah, it's a higher dimension. Next question.
9:31 Speaker 01 Oh, and not the fifth dimension, as in the singing group.
9:35 Neil deGrasse Tyson? Right, actually, there's a fifth dimension in there somewhere, but if you take the three dimensionality of our universe, and then you embed it among other universes in another kind of space, that's a higher dimension. And in fact, I hosted a panel on nothing.
9:51 Speaker 01 You hosted a panel on Seinfeld?
9:54 Neil deGrasse Tyson? On, on nothing at my host institution, the American Museum of Natural History, and we talked about what is between galaxies if the multiverse produces galaxies. And that's a kind of nothing, but it turns out it's not the best nothing that you can come up with.
10:09 Speaker 01 It's like the dark alleys of the universe?
10:10 Neil deGrasse Tyson? No, because that still has dimensions.
10:12 Speaker 01 Oh.
10:13 Neil deGrasse Tyson? Is it nothing if nothing's there, but it still has a dimensionality? See, we got really deep. I mean, heads were exploding left and right.
10:20 Speaker 01 Yeah.
10:21 Neil deGrasse Tyson? In the aisle.
10:22 Speaker 01 Like now.
10:23 Neil deGrasse Tyson? So, so, no, it's, it's, it's what we would call the space of a higher dimension, which is not even our space, because it would not have the matter, it would not have the energy, it would not have the, anything that we associated with our stuff, or even with where our stuff isn't. Because outside of our universe, there's not even the nothing of space.
10:44 Speaker 01 Wow, no?
10:47 Neil deGrasse Tyson? Well, because if space is nothing, then where there is no space, there's not even that nothing.
10:52 Speaker 01 Okay, next question.
10:54 Neil deGrasse Tyson? Okay.
10:55 Speaker 01 I'm sorry, I'm not allowed to call next question.
10:57 Neil deGrasse Tyson? All right, no, go for it, go for it.
10:58 Speaker 01 Because I'm just, what?
10:59 Neil deGrasse Tyson? Um, go for it.
11:00 Speaker 01 I need to go back to school. Okay, Edwin Martinez.
11:04 Neil deGrasse Tyson? There's nothing wrong with you, because you can't imagine higher dimensions than the ones in which we are embedded.
11:08 Speaker 01 I, I imagine higher dimensions, but.
11:10 Neil deGrasse Tyson? No, here's a way, I'll help you out. I'll hook you up, ready?
11:13 Speaker 01 Yeah.
11:14 Neil deGrasse Tyson? All right, so you take, take an ant and put him On a piece of paper and then draw a box around the ant.
11:17 Speaker 01 Okay.
11:18 Neil deGrasse Tyson? With a with a sharpie, alright, and say, ant, you can't leave the page.
11:21 Speaker 01 Oh, that's not gonna work.
11:22 Neil deGrasse Tyson? Alright, and so you just tell that to the ant, and the ant says, okay. And so the ant walks around, it hits the this line that you drew, and it can't get past it. And it's a prisoner in your sheet of paper, surrounded by this square drawn by your sharpie. Because the ant is embedded as part of the two dimensional world you just created for it. And you and you can say, well, just escape. I can't escape. Just jump out of the page. Step over the line and then go back into the page. And the ant says, I don't know what out of the page means. This is my universe.
11:55 Speaker 01 Wow.
11:55 Neil deGrasse Tyson? So now I put you in prison, surrounded not by a square that was containing the ant. I surround you by a cube. Six walls. And you say, I can't get out. But from a higher dimension, that person say, just step out into the higher dimension. Step back in and you've escaped. And you see, I have no idea what you're talking.
12:15 Speaker 01 No, no, I actually do. And I'm totally getting, I mean, I'm imagining. That's why the pictures move in Hogwarts, because they can step out of their dimension.
12:23 Neil deGrasse Tyson? You step out of your dimension, and then the walls no longer contain you.
12:27 Speaker 01 Oh, man.
12:28 Neil deGrasse Tyson? Yeah, so you step out of our dimension, you get to see things you would not otherwise have even known were there. Perhaps even the multiverse itself. Next question, Leanne.
12:38 Speaker 01 I'd love, I just wanna bask in that, but I'll move on.
12:41 Neil deGrasse Tyson? Basking doesn't work on radio?
12:43 Speaker 01 No, it doesn't. That's why I'm moving on. Edwin Martinez wants to know, uh, why is energy, uh, considered different from mass? And how is it that photons or waves are able to travel but yet have no defined mass? Uh, should not something have a mass if it's ejected and has a defined speed?
12:59 Neil deGrasse Tyson? Yeah, so photons have a mass equivalent.
13:02 Speaker 01 Okay.
13:03 Neil deGrasse Tyson? You plug their energy into which equation?
13:05 Speaker 01 E equals mc squared?
13:06 Neil deGrasse Tyson? Exactly, so their energy on one side. And a c squared is the speed of light squared. So you take that, remember your algebra, bring that to the left side. You divide both sides by c squared. So you have E over c squared equals m.
13:21 Speaker 01 Okay.
13:21 Neil deGrasse Tyson? All right.
13:21 Speaker 01 Yes.
13:21 Neil deGrasse Tyson? Right. If you remember your algebra.
13:23 Speaker 01 Yeah, yeah, yeah.
13:24 Neil deGrasse Tyson? That's like learn that in the fourth grade.
13:25 Speaker 01 I'm rolling.
13:26 Neil deGrasse Tyson? All right, so.
13:27 Speaker 01 Well, maybe in your school. I didn't give mine until sixth grade, but you know, whatever.
13:30 Neil deGrasse Tyson? So you got that, and so you put it, plug in the energy, you divide by c squared. That will tell you how much mass equivalent that energy has. And once you have the mass, you can plug that into a gravity equation. And that will tell you how much gravity the energy has. And so they work back and forth with one another. The difference is, once you become energy, if you're electromagnetic energy like light, then you move at the speed of light. I mean, you move at very high speeds.
13:59 Speaker 01 Okay.
13:59 Neil deGrasse Tyson? At the speed of light. If you have material substance, you cannot move at that speed. That's a problem. So what should you rather be? Light, uh, light energy or mass energy or mass?
14:11 Speaker 01 Light energy. Good, duh.
14:13 Neil deGrasse Tyson? Duh, okay.
14:14 Speaker 01 That's easy. Oh, finally, a question I can answer. Um, moving on.
14:18 Neil deGrasse Tyson? All right.
14:18 Speaker 01 I have a.
14:19 Neil deGrasse Tyson? Oh, by the way.
14:19 Speaker 01 Well, yes, by the way.
14:20 Neil deGrasse Tyson? As you move faster, time slows down for you?
14:23 Speaker 01 Well, yeah.
14:23 Neil deGrasse Tyson? Yeah. Duh.
14:26 Speaker 01 See, here's a, you know, when I actually know something, I have to revel in it.
14:29 Neil deGrasse Tyson? Okay, all right. So Einstein's relativity, when you, when you speed up, your time slows down relative to others who are watching you. And the closer you get to the speed of light, the slower time moves for you. At the speed of light, time stops, which means photons of light do not move forward in time.
14:50 Neil deGrasse Tyson? They live forever because they have no clock.
14:55 Speaker 01 Because they're moving at the speed of light?
14:56 Neil deGrasse Tyson? Correct.
14:58 Speaker 01 Did I just say that?
14:59 Neil deGrasse Tyson? Next question.
15:00 Speaker 01 Oh, my God. So does this have any reason why, uh, on Star Trek, the Enterprise's photon torpedoes don't work? Or this is, these are different photons?
15:08 Neil deGrasse Tyson? Uh, no. Here's the problem with a photon torpedo. If it's the energy going forward, you wouldn't see it from the side. That's just an FYI.
15:15 Speaker 01 Yeah.
15:16 Neil deGrasse Tyson? It's empty space. It's just, the energy's not coming to you, the viewer, it's going to the target.
15:21 Speaker 01 Right.
15:21 Neil deGrasse Tyson? So the photon torpedo should be invisible to anyone who is not getting hit by the photon torpedo.
15:27 Speaker 01 Of course.
15:28 Neil deGrasse Tyson? Yeah, otherwise you're wasting the energy illuminating my sightline for energy you're trying to deposit in the target.
15:36 Speaker 01 And the entire special effects department just got fired.
15:38 Neil deGrasse Tyson? I just did FYI on that one. It's the same with the phasers. If it's directed energy, you don't want energy leaking out the side of it.
15:46 Speaker 01 Right.
15:46 Neil deGrasse Tyson? Unless there's like someone hit two chalkboard erasers together along the path between the Enterprise and the target, and then it would illuminate the chalk dust.
15:56 Speaker 01 Right, right, of course.
15:56 Neil deGrasse Tyson? Along the way.
15:57 Speaker 01 Wow, that's very imaginative. Um, all right, I have another question.
16:01 Neil deGrasse Tyson? Yeah.
16:01 Speaker 01 I have a question from Natalie Dangle.
16:03 Neil deGrasse Tyson? Mm-hmm.
16:03 Speaker 01 Dagle. Uh, approximately, how many stars are born and die each day?
16:08 Neil deGrasse Tyson? Oh, I love that.
16:09 Speaker 01 Now, what's a day?
16:10 Neil deGrasse Tyson? Ah.
16:11 Speaker 01 How are we defining a day?
16:12 Neil deGrasse Tyson? I'm assuming Earth Day.
16:13 Speaker 01 Let's assume.
16:14 Neil deGrasse Tyson? And not somebody else's day, Earth.
16:16 Speaker 01 Earth.
16:16 Neil deGrasse Tyson? Right. But of course, other planets have days.
16:19 Speaker 01 Mm-hmm.
16:19 Neil deGrasse Tyson? Yes, in fact, Venus's day is longer than its year. Just chill on that one for a bit. So, Leanne's face just scrunched up in a, like.
16:31 Speaker 01 Cause I'm chewing on it. I'm actually chewing on it. That's okay.
16:34 Neil deGrasse Tyson? On Venus, the day lasts longer than a year, but we'll get back to that if, if we go there. So, now where was I before I distracted myself?
16:41 Speaker 01 How many stars?
16:42 Neil deGrasse Tyson? How many stars were born each day? So, you can do what's called a back of the envelope calc- calculation.
16:47 Speaker 01 Mm-hmm.
16:47 Neil deGrasse Tyson? You ready? All right.
16:48 Speaker 01 Yes.
16:48 Neil deGrasse Tyson? Our galaxy has about, just say a hundred billion stars.
16:52 Speaker 01 Mm-hmm.
16:53 Neil deGrasse Tyson? Okay? And the universe has been around for about 10 billion years. Back of the envelope means you change the number to make the math easy, but your answer will be.
17:01 Speaker 01 I back of the envelope my taxes all the time.
17:04 Neil deGrasse Tyson? So, but your answer will be approximately correct, and later on, you could put the exact number in if you want the exact answer.
17:10 Speaker 01 Fine, too.
17:10 Neil deGrasse Tyson? So, say we have about 100 billion stars, and the universe, and the galaxy's been around for 10 billion years. Okay? So, we have 100 billion stars, and we've been around for 10 billion years. That means the galaxy makes 10 stars a year.
17:25 Speaker 01 That's an average.
17:26 Neil deGrasse Tyson? Yeah, on average. That's right. If it made 10 stars a year, throughout his whole life, we'd have 100 billion stars over the 10 billion years. That's how that works. So, it makes about 10 stars a year, so that's about one a month. And so, we don't quite make a star a day, on average. About one a month. We could live with that. However, that's not actually how stars are born. They're born episodically, in stars, in stellar nurseries, where thousands of stars are born all at the same time. So, if you were a planet in orbit around one of those stars, you'll see stars lighting up daily as they are born.
18:00 Speaker 01 It must be pretty.
18:01 Neil deGrasse Tyson? Well, not daily, but frequently.
18:03 Speaker 01 Like, poof, there's Brad Pitt. And, poof, there's Angelina Jolie.
18:07 Neil deGrasse Tyson? A reminder that we had the stars first, before there were Hollywood stars.
18:11 Speaker 01 Oh, well, of course. Of course.
18:13 Neil deGrasse Tyson? We've got like, half a minute left. What do you got? What can we fit in here in this segment?
18:17 Speaker 01 Um, wow. Okay, I'll try. Uh, this is from Abdali. I can't even get the name out that quick. All right, here's a simple question. The moon orbits the earth, the earth orbits the sun, our solar system orbits the center of the Milky Way galaxy. Does this pattern stop on a galaxy level? Or is our galaxy orbiting something else? And that's from Chris Carlson.
18:35 Neil deGrasse Tyson? Cool question. I can do that in five seconds.
18:38 Speaker 01 Listening.
18:39 Neil deGrasse Tyson? Four, three. No, I can't do it. I'm gonna come back. What does our galaxy orbit? When we come back to StarTalk Radio, the Cosmic Queries Edition.
19:08 Neil deGrasse Tyson? This is StarTalk Cosmic Queries. I'm your host, astrophysicist Neil deGrasse Tyson.
19:15 Neil deGrasse Tyson? If you never knew it, my day job is as director of the Hayden Planetarium here at the American Museum of Natural History in New York. Come by and visit. Tell the front gate that you know me and they'll still charge you admission. Just an FYI. So, Leanne Lord, I got you in studio. Thanks for reading Cosmic Queries to me.
19:32 Speaker 01 Oh, no, thank you.
19:33 Neil deGrasse Tyson? And these are dark things in the universe, dark mysteries of the cosmos.
19:36 Speaker 01 Dark mysteries of the cosmos.
19:37 Neil deGrasse Tyson? And we almost, we just didn't have time in that last segment. What was that last question?
19:40 Speaker 01 All right, that last question, again, was from Chris Carlson, and basically, the moon orbits the earth, the earth orbits the sun, and our solar system orbits the center of the Milky Way. So, does this pattern stop on a galaxy level, or is our galaxy, among others, orbiting something else?
19:55 Neil deGrasse Tyson? We technically are orbiting the Andromeda Galaxy. Oh, by the way, we should be clear. The moon doesn't orbit the earth.
20:03 Speaker 01 Okay.
20:04 Neil deGrasse Tyson? They... The moon doesn't orbit the earth. The moon and earth orbit a common center of gravity.
20:12 Speaker 01 Yes.
20:13 Neil deGrasse Tyson? Which is not in the center of the earth. In fact, it's 1,000 miles below earth's surface, on a line between the center of the earth and the moon, wherever the moon is at any time.
20:23 Speaker 01 Got it.
20:24 Neil deGrasse Tyson? But we're 4,000 miles in radius. So, 1,000 miles down is not the center of the earth. So, while the moon goes around us, we do a kind of a jig. We do a little jiggle. All right?
20:36 Speaker 01 The Earth shimmy, the Earth Harlem Shake?
20:39 Neil deGrasse Tyson? The Earth kind of shimmies, because the point that it revolves is within itself, and it's not at its center. So, you got that, all right?
20:47 Speaker 01 Okay.
20:48 Neil deGrasse Tyson? Meanwhile, earth and the moon go around the sun, a common center of mass between the two of them, which is not at the center of the sun.
20:59 Speaker 01 I'm sensing a pattern here.
21:01 Neil deGrasse Tyson? Except, we are so schmaltzing compared to the sun, that the center of mass between the sun and the earth is really close to the center of the sun.
21:08 Speaker 01 Okay.
21:09 Neil deGrasse Tyson? Okay? The sun is so large, a million earths can fit inside it. So, we're not really yanking the sun's chains here. But, the little bit that we do, that's how many planets are discovered orbiting other stars. You look at a star and the star is not just hanging out, it is shimmying. And you're saying, "We infer a source of gravity that's orbiting that shimmying star." And the amount it shimmies tells you how far away the planet is from it and how much mass it contains. So, yeah, so Earth and Moon, common center of gravity. Earth, Moon, and the Sun, common center of gravity. The Sun and the center of the galaxy, we orbit that.
21:51 Neil deGrasse Tyson? The galaxy is technically in orbit with the Andromeda Galaxy together. Except our orbits are really elongated. They're not circular.
22:00 Speaker 01 No.
22:00 Neil deGrasse Tyson? They're like, they're so elongated that in fact, we're on a collision course.
22:04 Speaker 01 Really?
22:05 Neil deGrasse Tyson? Yes, we will collide with Andromeda in about seven billion years.
22:09 Speaker 01 Alright, let me mark my calendar.
22:10 Neil deGrasse Tyson? It will be a train wreck, a Titanic collision. Mark, you put it in your, your, your, your smartphone, you'll have it.
22:18 Speaker 01 Alright.
22:18 Neil deGrasse Tyson? Yeah.
22:18 Speaker 01 Shall we move on?
22:19 Neil deGrasse Tyson? Yes.
22:20 Speaker 01 Alright, this is from Lexi Davis, this is a cute question, I love this. Uh, "Is there anything smaller than the infinitely small? And can you put it in a way that does not make me hate that I don't even get to be in pre-calc till next year?"
22:33 Neil deGrasse Tyson? Ooh, high school student.
22:35 Speaker 01 Yes! Can you smell that? Young person.
22:40 Neil deGrasse Tyson? Uh, yeah, so, uh, by the way, see, if you really like math, see if you can skip pre-calc and just go straight to calc. Just, just, tell them Tyson told you.
22:49 Speaker 01 Tyson told. I have a, I have a note from my personal astrophysicist, can I please get in?
22:54 Neil deGrasse Tyson? And just go, see if you can go straight to calc. But, alright, so, is there anything smaller than infinitesimally small?
22:59 Speaker 01 Mm-hmm.
23:00 Neil deGrasse Tyson? Uh, yes.
23:02 Speaker 01 Alright, next question. You are so evil.
23:05 Neil deGrasse Tyson? Okay, no, no, so here it is. Uh, "The electron is smaller than the smallest thing we have ever measured. And in fact, it is so small, we do not know how small it is. We cannot measure it, it is so small. In fact, it could be so small as to not occupy any volume at all. As far as our measurement devices are concerned, it has no dimensions at all. The electron." So, the electron comes closest to infinitesimally small of anything we have ever known, thought of, dreamt of, or measured.
23:49 Speaker 01 Okay. So.
23:51 Neil deGrasse Tyson? Yeah, so.
23:52 Speaker 01 Got it.
23:52 Neil deGrasse Tyson? There you go. What else you got?
23:54 Speaker 01 I have a question from Paul Lundgren.
23:56 Neil deGrasse Tyson? Uh huh.
23:57 Speaker 01 And he says, can a brown dwarf? What are you doing? No, okay, I'm moving on. Can a brown dwarf accumulate enough?
24:03 Neil deGrasse Tyson? Yeah, don't go there.
24:04 Speaker 01 I'm not, yeah, I thought about it and I'm like, nah, I like my job. Can a brown dwarf accumulate enough matter to ignite itself into a star? And then he says, corollary, can a neutron star gather enough additional mass to collapse into a black hole?
24:18 Neil deGrasse Tyson? Well, corollary, that person actually used the word corollary?
24:21 Speaker 01 Corollary, sir.
24:22 Neil deGrasse Tyson? Corollary, very nice.
24:24 Speaker 01 That is our SAT word of the day from Paul Lundgren.
24:27 Neil deGrasse Tyson? So, a brown dwarf is a failed star. Didn't have enough mass to make its center hot enough.
24:31 Speaker 01 It's a muggle?
24:34 Neil deGrasse Tyson? To, so the center never got hot enough to engage nuclear fusion. And so it kind of withers there, giving up the little bit of heat it did accumulate on collapse. I know. So they're asking, if you sort of fed it matter, would you, could you ignite the center and turn it into a star? Yes. And that would be awesome. If we had the power over stars, you could, you can turn off some stars, turn on other stars. And in fact, you could do that with Jupiter. Jupiter is about one tenth, a little less than one tenth, the mass necessary for a star.
25:03 Speaker 01 Mm hmm.
25:04 Neil deGrasse Tyson? If you start feeding it material, that puppy will grow, get hot in the middle, bam! We'll have a two star solar system.
25:11 Speaker 01 Wow.
25:11 Neil deGrasse Tyson? Oh, yeah, that would, that would be good. And, uh, and the other one was about the neutron star. We'll get back to neutron star after this break.
25:21 Speaker 01 Oh, great.
25:21 Neil deGrasse Tyson? Can we do something with a neutron star by adding matter to it? We'll see in a moment.
25:43 Neil deGrasse Tyson? We're back. StarTalk Radio, after hours. Cosmic Queries Edition, Leanne Lord, thanks for being with me.
25:49 Speaker 01 Thank you.
25:50 Neil deGrasse Tyson? Excellent. So we're reading, uh, Dark Mysteries of the Universe.
25:53 Speaker 01 Yes.
25:54 Neil deGrasse Tyson? Questions I haven't seen.
25:55 Speaker 01 You have not seen.
25:55 Neil deGrasse Tyson? Hearing them for the first time. And we, at the break, we had an awesome question from a high schooler.
26:00 Speaker 01 Um, well, that was from Lexi. Um, I don't know if Paul is, uh, in high school or.
26:04 Neil deGrasse Tyson? Oh, okay, great. But we answered Lexi's question.
26:06 Speaker 01 We did answer Lexi's question and you.
26:08 Neil deGrasse Tyson? Well, I'm assuming she's in high school because she was talking about taking pre-calc.
26:11 Speaker 01 Pre-calc, right.
26:12 Neil deGrasse Tyson? Right, and you wouldn't really do that in elementary school. And you could be like a, a, a full-up adult going back to school.
26:18 Speaker 01 You could be.
26:18 Neil deGrasse Tyson? You could be, but I, I bet she's like in 10th grade or something like that.
26:22 Speaker 01 And you're advising straight to calculus.
26:23 Neil deGrasse Tyson? If you love it, just.
26:24 Speaker 01 Just fight no big dog.
26:25 Neil deGrasse Tyson? Yeah, don't know this pre-stuff. That's like preschool, just go straight to school.
26:29 Speaker 01 Straight to school. Directly to school. Do not fast go.
26:33 Neil deGrasse Tyson? Prenup, just go straight to the nup.
26:34 Speaker 01 Wow. No, no, no, he don't mean that, y'all. Get a prenup. Don't mess around. Get a prenup.
26:40 Neil deGrasse Tyson? All right.
26:41 Speaker 01 Well, it was Paul Lundgren who had a, a two-part question, and he wants to know if we could gather, could a neutron star gather enough additional mass to collapse into a black hole?
26:49 Neil deGrasse Tyson? Yes.
26:49 Speaker 01 All right, great.
26:50 Neil deGrasse Tyson? So a neutron star is, uh, below the mass, is the endpoint of a star's death, a high-mass star's death, and it didn't have enough mass. I say high mass, but it's not high enough to cram the material down in the middle to create a black hole beyond, a boundary beyond which the matter will never be seen again. So, uh, here's what, here's the problem. We think that if you just slowly deposit mass onto a neutron star, it will flare up. It might flare up rather than become a black hole. So you have to add it in a way that the whole thing knows about all the mass at the same time. Right? So that might be hard to do. In other words,
27:32 Neil deGrasse Tyson? it's not clear whether you can just feed it until it tipped its threshold.
27:36 Speaker 01 Oh, okay.
27:37 Neil deGrasse Tyson? You might have to add it all, add it all at once. But I'd have to check my equations on that, but that's my guess.
27:42 Speaker 01 Okay.
27:42 Neil deGrasse Tyson? Yeah.
27:42 Speaker 01 Because we don't know the tipping point?
27:44 Neil deGrasse Tyson? That, yeah, because you just put on a little bit at a time, that might flare up on its own and then it, it's gone. It blows itself away.
27:50 Speaker 01 Oh.
27:50 Neil deGrasse Tyson? Yeah, that's how the original stuff left. It, the original star that exploded and left behind the neutron star blew up. That's what happened. So I, I, I think you'd have to need a scheme to add it all at once.
28:02 Speaker 01 Hmm, okay.
28:03 Neil deGrasse Tyson? Yeah.
28:04 Speaker 01 Uh, as with everything else, I'm taking your word for it.
28:06 Neil deGrasse Tyson? Uh-huh. Oh, by the way, neutron star is really dense. I mean, it's, it's.
28:11 Speaker 01 It's not smart?
28:13 Neil deGrasse Tyson? So it's, uh, you know, dense, uh, heavy dense. And I tweeted, because I swear in the movie Thor, the guy said that Thor's hammer was forged of the material of a dying star. And I said, cool, I can calculate how heavy the hammer must be.
28:29 Speaker 01 So only you would sit there in the theater.
28:32 Neil deGrasse Tyson? No, no, I said, I can so do this. And so, but I didn't know the dimensions of the hammer. And so a friend of mine got me a Thor's hammer to borrow. I would have to give it back in the morning. And so I got, I got Thor's hammer. And so I measured it up and I said, okay, well, this is, this is pretty awesome. And I forgot the number I got. It was something like the hammer. If you crammed a herd of 60 billion elephants into the volume of that hammer, it would weigh about the same as the hammer. And so that's why the Hulk couldn't lift it. And I was, so I tweeted that. I showed a picture of me holding the hammer. And then someone geekier than I am, a professor of physics.
29:09 Speaker 01 This person exists?
29:11 Neil deGrasse Tyson? Who's a Thor enthusiast, said, no, it's not forged of neutron star matter. It's not forged of the material of a dying star. It's forged in the material of a dying star, but it's made of some other stuff that is in fact as light as feathers. So I said, well, that's no fun. The hammer weighs as much as feathers. And then therefore it's really the magic god power that prevents you from lifting it or enables you to lift it. So I thought that was nowhere near as interesting as my elephant.
29:39 Speaker 01 No, no, not at all. It all turns on an article.
29:42 Neil deGrasse Tyson? But I will in and of, but I'll defer. I mean, I got, you gotta defer to the folks who like live for this stuff. So go on, that's my, that's my aside on the neutron star, but go on.
29:53 Speaker 01 That is amazing. I, you know what? You still had me at the fact that somebody got you the hammer. This is totally not legal.
29:58 Neil deGrasse Tyson? I saw, I saw cool. It's got the leather strap and everything. Oh, yeah.
30:01 Speaker 01 Oh, my God. Very sexy. All right, um, I have more questions.
30:06 Neil deGrasse Tyson? Mm hmm, go for it.
30:06 Speaker 01 We do here, um, from George Beardston. How does the Higgs feel different from earlier ideas of an ether?
30:13 Neil deGrasse Tyson? Oh, did you spell ether right? A E?
30:16 Speaker 01 Yes, yes. The A is silent.
30:18 Neil deGrasse Tyson? Uh, a science, it's a dipthong.
30:20 Speaker 01 It's a dipthong.
30:21 Neil deGrasse Tyson? Yeah, I think it's a dipthong.
30:22 Speaker 01 That's very kinky.
30:23 Neil deGrasse Tyson? Yeah.
30:26 Neil deGrasse Tyson? They should invent a new bathing suit, the Dipthong, you know? That would be cool. So let me see, we only have like 20 seconds left.
30:33 Speaker 01 Yeah, because you're fooling around.
30:34 Neil deGrasse Tyson? Let me see, well, I have to give half the answer and you're going to get the full answer at the end of the break. But the ether was this proposed medium of the cosmos through which light traveled. Because people knew that light was a wave and sound is a wave and you, sound doesn't move through a vacuum, does it? You ever remember the bell jar experiment where you have a bell ringing? You put a jar over it, you evacuate all the air and the bell shuts off. The bell is ringing and you can't hear it.
31:02 Speaker 01 Right.
31:02 Neil deGrasse Tyson? It doesn't go through a vacuum, so neither should light, was the hypothesis. When we come back, more on the answer to that question on StarTalk.
31:29 Neil deGrasse Tyson? StarTalk, Cosmic Queries, this is the last segment.
31:33 Speaker 01 It is. This goes by way too fast.
31:35 Neil deGrasse Tyson? And this is normally our lightning round and it will be, but I left a question hanging out there. So the ether was about, is the Higgs field like the ether of yesteryear perhaps? Is that, was that how that question?
31:46 Speaker 01 Yeah, yeah, yeah. How does the Higgs field differ from earlier ideas of the ether?
31:49 Neil deGrasse Tyson? Yeah, because the ether was a thing. Nobody knew what it was.
31:51 Speaker 01 Right.
31:52 Neil deGrasse Tyson? That was proposed to allow light to vibrate its way from a star to us through the vacuum of space.
31:57 Speaker 01 Okay.
31:57 Neil deGrasse Tyson? Because sound needs something to vibrate, the ground, the air. Sound doesn't travel through space, such was the tagline to the movie Alien in space.
32:06 Speaker 01 We can hear you scream.
32:08 Neil deGrasse Tyson? Yes. However, light travels through it, so surely there must have been a medium out there through which light can move and vibrate. And it was proposed to be the ether, but it was never found, never measured. It was never found, so, and it went away.
32:21 Speaker 01 So is the ether dark matter?
32:22 Neil deGrasse Tyson? No, we learned that this, that light does not require any medium at all to vibrate, it is self vibrating.
32:28 Speaker 01 Oh, man.
32:29 Neil deGrasse Tyson? Don't go there, stop.
32:32 Speaker 01 Ooh, it hurt. That actually physically hurt.
32:35 Neil deGrasse Tyson? I'm just talking universe here.
32:37 Speaker 01 Drain myself.
32:38 Neil deGrasse Tyson? I'm just universe.
32:39 Speaker 01 Is it warm in here?
32:41 Neil deGrasse Tyson? So this is the lightning round. Lightning round cosmic crazy. Let me get my bell. See, we'll check it. There we go.
32:49 Speaker 01 All right.
32:49 Neil deGrasse Tyson? So let's see how many questions we can get through in this final.
32:53 Speaker 01 All right.
32:53 Neil deGrasse Tyson? Go.
32:54 Speaker 01 Ready?
32:54 Neil deGrasse Tyson? Yes.
32:55 Speaker 01 Mike Thorson, what is the speed of gravity?
32:57 Neil deGrasse Tyson? Speed of gravity is the same as the speed of light. Hundred and eighty six thousand, two hundred and eighty two miles per second.
33:03 Speaker 01 Nice. Jesus Perez.
33:04 Neil deGrasse Tyson? I'm sorry. That's the speed of a change of gravity. If you jiggle the space time continuum, that ripple will move at the speed of light.
33:12 Speaker 01 Jiggling the space out. Listen. Jesus Perez, how do you know math is?
33:17 Neil deGrasse Tyson? Jesus.
33:18 Speaker 01 Jesus Perez.
33:21 Neil deGrasse Tyson? You can say Jesus. Oh, wow. Jesus reads our web pages.
33:24 Speaker 01 Of course he does. Jesus is literate. How do you know math is the language of the universe?
33:28 Neil deGrasse Tyson? How do we know? Because the universe tells us. Eugene Wriggar, a physicist back in the 20th century, commented on the unreasonable effectiveness of mathematics.
33:39 Speaker 01 The unreasonable effectiveness.
33:41 Neil deGrasse Tyson? Because we invented it, yet it accounts for the operations and motions of the universe. Since math is purely logical, it means the universe at its finest is logical.
33:51 Speaker 01 The math is Vulcan. Love it. Lionel Lyman wants to know, can you explain zero point space?
33:58 Neil deGrasse Tyson? Oh, yeah. So the vacuum of space is not actually empty.
34:04 Speaker 01 It's not.
34:04 Neil deGrasse Tyson? No, there is because of quantum physics. Every spot in that vacuum has a certain chance of having energy associated with it. Non-zero energy and particles pop in and out of existence there. And it's called the zero point energy. And space enthusiasts, science fiction enthusiasts want to one day tap that energy and drive spaceships through the vacuum of space without having to go back and refuel. But I think that's unlikely.
34:30 Speaker 01 Yeah.
34:30 Neil deGrasse Tyson? Because you can't access it. It's not accessible energy to you. But that's zero point energy. That's what that is.
34:36 Speaker 01 Nice. Kirk Wilkinson wants to know.
34:39 Neil deGrasse Tyson? Wait, wait, wait. Oh, no, no. Sorry. Sorry. That's vacuum energy. Undo. Can we undo the bell?
34:44 Speaker 01 Undo the bell. Undo the bell.
34:45 Neil deGrasse Tyson? So I just described vacuum. I haven't seen these questions. That's vacuum energy, that the energy of the vacuum. Zero point energy is if you chill something to zero degrees where there's no energy left in it, there's still energy left in it. Right, cuz something has a
35:00 Speaker 01 How is that not a contradiction?
35:01 Neil deGrasse Tyson? Something has temperature because its molecules vibrate. Lower the temperature, they vibrate less.
35:06 Speaker 01 Right.
35:06 Neil deGrasse Tyson? Lower it more, they vibrate even less. Classically, if you took that temperature to zero, absolute zero, it's called. They wouldn't vibrate at all. All motion would stop. But quantum physics tells us they can't stop. They can never stop. And that is zero-point energy. Next.
35:21 Speaker 01 Nice. Kirk Wilkinson. If there's a supermassive black hole at the center of our galaxy, could the entire galaxy then be considered an accretion disk?
35:30 Neil deGrasse Tyson? Ooh, no, because we are not accreting to the black hole, thankfully. There's a gap between us and that black hole that is big enough, it ain't getting us.
35:39 Speaker 01 Nice.
35:40 Neil deGrasse Tyson? Yeah.
35:40 Speaker 01 We gonna, we gonna shift a little bit to Star Wars.
35:43 Neil deGrasse Tyson? Which means it's possibly far enough away from, it's possible to be far enough away from a black hole and never get sucked in at all. Go.
35:48 Speaker 01 Nice, good to know. I'll keep my distance. Adam Young wants to know, have we considered the consequences of tapping into the dark side of the force?
35:57 Speaker 01 And is the dark side of the force really stronger or just more loose?
36:02 Neil deGrasse Tyson? Ooh, well, all the forces we know don't have dark sides.
36:06 Speaker 01 You haven't met my mother.
36:09 Speaker 01 I'm sorry.
36:10 Neil deGrasse Tyson? So, yeah. There's, uh, there's the, there's a push-pull. There's an up, you know, there are forces that can move and shrink and things, but we don't put, uh, emotional, cultural interpretations upon them. They're just forces.
36:23 Speaker 01 Nice. All right. Uh, this is an email from, oh, I can't see what it's from. Oh, it's from Paul Leonard.
36:29 Neil deGrasse Tyson? Oh, by the way.
36:30 Speaker 01 Yes.
36:30 Neil deGrasse Tyson? If we did, then you'd know they would have to be evil. Otherwise, you could not define any force as good.
36:38 Speaker 01 This is another show.
36:40 Neil deGrasse Tyson? Okay, go.
36:40 Speaker 01 If every action, this is from Paul Leonard. If every action or decision can spawn an alternate, an alternate universe, where does this universe worth of matter and energy come from? And this guy's been losing sleep over this.
36:52 Neil deGrasse Tyson? It has been hypothesized that at every point you can choose to make something happen, you choose to do so, but another universe spawns that continues the way you would have existed in that other way. Yes. This is the multi-universe hypothesis of quantum physics. Sliding doors, got it. Yeah, yeah. And so that was a way to understand how an experiment can have multiple simultaneous outcomes. Yes. Right? Maybe the universe split, but no one takes that literally seriously. It's just a way to explain stuff that we have no clue what it is that's actually doing. That's why quantum mechanics remains seriously mysterious even to experts. That is all the time we have for Cosmic Queries. Leanne, thanks for being on the show. Thank you. Brought to you in part by a grant from the National Science Foundation.
37:37 Neil deGrasse Tyson? You've been listening to StarTalk Radio. I'm Neil deGrasse Tyson, telling you, as always, to keep looking up.
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