Cosmic Queries – Galactic Grab Bag – Blue Steel

Summary

StarTalk Radio: Cosmic Queries – Galactic Grab Bag – Blue Steel

Host: Neil deGrasse Tyson
Co-host: Chuck Nice
Date: January 16, 2026

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Episode Overview

In this lively "Galactic Grab Bag" (formerly known as "Galactic Gumbo") edition of StarTalk Radio, astrophysicist Neil deGrasse Tyson and comic co-host Chuck Nice tackle a diverse array of listener-submitted science questions. From lunar motions to the quirks of the periodic table, terraforming Mars to the fate of photons, this episode blends accessible explanations with trademark humor and pop culture references. The show highlights the fluidity between science and culture, navigating everything from astronomy fundamentals to the fun of movie cameos.

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Highlights & Key Discussion Points

1. Galactic Grab Bag—What’s In a Name?

Timestamps: [01:11]–[01:55]

• The hosts reminisce over the segment’s former names, including "Cosmic Potpourri" and "Galactic Gumbo," before settling on "Grab Bag," likening it to the unpredictability of a holiday present exchange.

2. Moon’s Wobble and Libration

Timestamps: [03:28]–[08:02]

• Listener Question: What’s the Moon’s "wobble" and how does it affect Earth?
• Neil’s Deep Dive: Clarifies the interesting phenomenon is libration, not wobble; explains how the Moon’s elliptical orbit and tidal locking result in us seeing more than 50% of its surface over a "moonth."
• Quote:

  "When you look at time-lapse photos of the Moon, it is striking to behold. The Moon is like, turning a little to the left to you, a little to the right. So we can see more than 50% of its surface over the duration of a moonth." — Neil deGrasse Tyson [06:40]

• Fun Fact: "Moonth" is the etymological root of "month."

3. Pop Culture Sidebar: ‘Zoolander’ & The Blue Steel

Timestamps: [08:08]–[10:16]

• Chuck riffs on "Blue Steel” (a ‘Zoolander’ reference), sparking laughs about Neil’s cameo in “Zoolander 2” and his reputation for ending movie franchises.
• Quote:

  "I've been in four movie franchises, okay? And for three of them, there were no more movies made after." — Neil deGrasse Tyson [09:09]

  "So I was in Ice Age 5, okay, and the critic said it’s about time the series went extinct, like all the creatures in it." — Neil deGrasse Tyson [09:27]

4. Has Humanity Always Seen the Same Night Sky?

Timestamps: [10:32]–[13:26]

• Listener Question: Has the night sky changed for humans in the last ~150,000 years?
• Neil’s Response:
  • Stars are in motion and constellations would have looked different (notably, about half the night sky would be unrecognizable); the Big Dipper, for example, is a cluster whose shape would be completely different 75,000 years ago.
• Quote:

  "If you go back 75,000 years...you would not recognize most of the constellations of the night sky." — Neil deGrasse Tyson [12:39]

5. The Curious Case of Mercury (the Element) Being Liquid

Timestamps: [13:32]–[24:44]

• Listener Question: Why is mercury liquid at room temperature, when neighboring elements are solid?
• Neil’s Nuanced Take:
  • Explains the periodic table and role of quantum physics in elemental properties.
  • Admits there isn't a simple answer—melting point is not a chemical property; "being liquid is not the most different thing about an element."
  • Ambient temperature is arbitrary; different lab conditions in different countries led to different "liquid" vs "solid" classifications for some elements.
• Quote:

  "If you want to think of the periodic table as some deep fundamental truth about the universe, then you should not be distracting yourself about whether it's solid, liquid, or gas at your laboratory temperature, because the universe doesn't give a rat's ass about your laboratory temperature." — Neil deGrasse Tyson [23:17]

6. States of Matter in the Universe

Timestamps: [23:49]–[26:20]

• Discussing how water, methane, and other substances can be solid, liquid, or gas depending on environmental conditions—what we consider "normal" is only true under specific circumstances.
• Quote:

  "On Earth, that's gaseous, you go to Saturn's moon, Titan...it liquefies methane. And the water, it is so cold that the water has frozen so solid that it's basically the bedrock." — Neil deGrasse Tyson [24:49]

7. Terraforming Mars: What’s Holding Us Back?

Timestamps: [26:24]–[30:18]

• Listener Question: Can we actually terraform Mars with its dead core and lack of a magnetic field?
• Neil’s Take:
  • Living underground or shielding from the sun solves some UV and solar wind concerns.
  • Technological capacity (“geoengineering”) might even let us restart Mars’ magnetic field by stirring the core.
  • The real challenge isn’t blocking radiation—it’s creating a functional, sustainable biosphere.
• Quote:

  "If we have the power of geoengineering to turn Mars into an arable place, I don't see why we couldn't figure out some way to deflect the solar wind...engineers tend to solve problems when given the task." — Neil deGrasse Tyson [28:43]

8. Best Spots in the Solar System for Astronomy

Timestamps: [33:33]–[37:17]

• Listener Question: Are there better places than Earth for unobstructed astronomical observation?
• Key Points:
  • The Moon is a huge source of nighttime brightness; astronomers compete for "dark time."
  • Earth’s radio noise is also a challenge; proposals exist to build radio telescopes on the Moon's far side, shielded from Earth interference.
  • Notable mention of the James Webb Space Telescope's location—far from both Earth and the Moon for optimal conditions.

9. Voyager and the Edge of the Solar System

Timestamps: [37:17]–[39:02]

• Clarifies that the solar system’s “boundary” is defined by the influence of the Sun’s magnetic field and particle wind; Voyager left this region, which is well past Pluto.

10. Fairness in Telescope Time & The Power of Discretionary Observation

Timestamps: [39:11]–[42:48]

• Listener Question: Do senior scientists get priority for telescope observation time?
• Answer:
  • Access is granted based on the brilliance of the idea—not seniority. Research papers don’t list degrees, and even undergrads can get credit for major discoveries.
  • Telescope directors do have "director's discretionary time" for bold or risky projects—like the famous Hubble Deep Field image.
• Quote:

  "Your seniority has nothing to do with it. It's how brilliant is your idea." — Neil deGrasse Tyson [39:49]

11. Do Photons “Experience” Time and Can They Decay?

Timestamps: [42:52]–[45:37]

• Explains that because photons travel at light speed, time does not progress for them—hence, they don’t "know" to decay. If photons experienced time, they wouldn’t be massless photons anymore.
• Quote:

  "If you have no measure of time, then you cannot know to turn into anything else later in life, because there is no later." — Neil deGrasse Tyson [44:22]

  "So it means the photon that we detect here that was emitted in the early universe shortly after the Big Bang, as far as it's concerned, it's still the Big Bang." — Neil deGrasse Tyson [45:06]

12. Black Hole Shrinkage and Visibility

Timestamps: [45:41]–[49:16]

• Listener Question: As black holes lose mass (via Hawking radiation), can they get small enough that light escapes and we see what’s inside?
• Neil’s Deep Dive:
  • Any mass can be a black hole if compressed enough; if a black hole loses mass, it simply shrinks, staying a black hole until the theoretical end.
  • At the end of its life (theoretical Hawking evaporation), it might produce a burst of gamma rays—physicists search for this in cosmic data.
• Quote:

  "The original Hawking radiation paper prompted people to look for little bursts of gamma rays...which could signal black holes dying, having completely evaporated." — Neil deGrasse Tyson [49:10]

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Notable Quotes & Memorable Moments

• Chuck Nice, laughing about Neil’s movie curse:

  "Could you please be in Fast and the Furious? Please be in that...I just want the last scene to be you, like, cruising, like, 'Yo, what up? Keep looking up.' But not while you're driving.” [10:16]

• On the arbitrary nature of ‘room temperature’ in science:

  "The universe doesn't give a rat's ass about your laboratory temperature." — Neil deGrasse Tyson [23:17]

• Defining the scientific enterprise:

  "If you don't have a clock, there's no reason or understanding we possibly have for why you would change into another [particle]." — Neil deGrasse Tyson [44:53]

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Final Thoughts & Tone

This episode is classic StarTalk: science-laden, quirkily humorous, and accessible. Neil and Chuck effortlessly mix deep dives into scientific nuances with pop culture tangents and self-deprecating laughs, all while celebrating curiosity, the scientific process, and the universality of wonder about the cosmos.

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Segment Timestamps

• [01:11] – “Grab Bag” banter
• [03:28] – Moon’s libration explained
• [08:08] – “Zoolander 2,” Blue Steel, and movie franchise jinx
• [10:32] – Has the night sky changed for humans over millennia?
• [13:32] – Mercury’s liquid state & the periodic table
• [23:49] – Matter states in varying planetary conditions
• [26:24] – Terraforming Mars: science & engineering hurdles
• [33:33] – Where astronomers go for perfect night sky observations
• [37:17] – Voyager’s exit from the solar system
• [39:11] – Telescope time: fairness & the Hubble Deep Field
• [42:52] – Do photons experience time or decay?
• [45:41] – Black holes evaporating: can we see “inside”?
• [49:27] – Wrap up and reflections

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Summary prepared for listeners who want a full, engaging yet structured recap—without having to press play.

Transcript

[Reggie]

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[Neil deGrasse Tyson]

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[Chuck Nice]

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[Neil deGrasse Tyson]

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[Neil deGrasse Tyson]

Terms apply. Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins. Ends right now. This is Star Talk Cosmic Queries edition. I got Chuck. Nice. My co host, Chuck.

[Chuck Nice]

Hey, Neil. What's happening?

[Neil deGrasse Tyson]

Chuck? This is grab bag.

[Chuck Nice]

It is indeed. We used to call it the cosmic potpourri. We used to call it cosmic gumbo, which was my favorite. Galactic, not cosmic.

[Neil deGrasse Tyson]

Galactic gumbo.

[Chuck Nice]

Galactic gumbo.

[Neil deGrasse Tyson]

You have to get that alliteration.

[Chuck Nice]

But now we have a grab bag, which it makes me wonder, where does that come from? Grab bag. You know, it means just like an assortment of pretty much miscellaneous items.

[Neil deGrasse Tyson]

Yeah. Yes. The presents in the holiday season where you reach in and grab and you don't know what you're getting. Is that really what it is from Santa Claus? Why wouldn't it be?

[Chuck Nice]

Okay, cool.

[Neil deGrasse Tyson]

Yeah.

[Chuck Nice]

Yeah. We called that Christmas.

[Neil deGrasse Tyson]

You've been in my office. I have a grab bag in there. That's a black hole, right? It actually says black hole on the side of says black hole. That's how you know it's a black hole. It says it.

[Chuck Nice]

Very nice. Very cool.

[Neil deGrasse Tyson]

That reminds me of completely off topic, but the discoverer of Pluto, his name is Clyde Tombaugh. My boy lived deep into his 90s because he wasn't letting go of Pluto any sooner than he was.

[Chuck Nice]

He was hoping that. He was hoping that it would happen.

[Neil deGrasse Tyson]

He was. He was trying to keep it.

[Chuck Nice]

Yeah. On his deathbed, they told him, you did it. It's a planet. And he was just like, oh, thank God. And why'd you lie to him? He's dying. He's dead.

[Neil deGrasse Tyson]

He's dead. He's dead.

[Chuck Nice]

What do you mean, why did I lie? To him, that's like somebody's dying. And you say to him, you know, I never loved you, right? No.

[Neil deGrasse Tyson]

Long time to report that information. Exactly.

[Chuck Nice]

It's like, he's dead. Like, let him. You know, I loved you so dearly my entire life. I shall miss you. And then they die, and you're like, oh, thank God.

[Neil deGrasse Tyson]

So he. So he was asked, what did it take to discover Pluto? You know, how hard was that? And he said, well, when I got the photos of the night sky, it was really easy because there was an arrow pointing to it.

[Chuck Nice]

Oh, that's hilarious.

[Neil deGrasse Tyson]

Every picture you've ever seen of Pluto.

[Chuck Nice]

There is an arrow. That's funny.

[Neil deGrasse Tyson]

So there you go. All right, so let's do this. Grab that. I assume anything under the sun and above it as well.

[Chuck Nice]

There you go.

[Neil deGrasse Tyson]

So let's go for it.

[Chuck Nice]

All right, here we go.

[Neil deGrasse Tyson]

Give it to me.

[Chuck Nice]

This is David Brian Smith. And he says. Yes, this is really my name, not just made up. So actually, you can pronounce it Chuck. Oh, you jerk. I should read these in advance. All right, David, you got me. He says, can you explain the Moon's wobble and how it affects the Earth? Interesting.

[Neil deGrasse Tyson]

Okay, well, so I don't think he's referring to the Moon's wobble, because that's not interesting. What's interesting? There's something called a libration. Not libation. Not libation.

[Chuck Nice]

Don't speak it. Is it anything like a liger?

[Neil deGrasse Tyson]

No.

[Chuck Nice]

Okay, a libration.

[Neil deGrasse Tyson]

A libration. Right. You mean liger, like the cross between a lion and a tiger?

[Chuck Nice]

Yeah. You ever see those things? They're huge.

[Neil deGrasse Tyson]

Yeah.

[Chuck Nice]

Yeah.

[Neil deGrasse Tyson]

No, that's not. This has nothing to do with that, Chuck.

[Chuck Nice]

Oh, I just heard lie.

[Neil deGrasse Tyson]

Okay, a libration. So what's happening is the Moon's orbit. Again, I'm assuming that's what he's referring to, because the Moon doesn't have a wobble that anyone cares about. So that's why. But there's an interesting libration. So what's happening is because the Moon's orbit around the Earth is not a perfect circle. It's an ellipse. It can get as close as 225,000 or so miles and as far as almost 250,000 miles. So it's a 25,000 mile range between when it's closest and when it's farthest. Okay. The Moon is also tidally locked to Earth, so it's always showing the same face. Okay. That's a natural phenomenon in the universe. And Systems of orbiting objects naturally descend into that state relative to each other. So that's fine, nothing weird going on there. Here's the problem, okay? If it were a perfectly circular orbit, you would only ever see exactly the same side and it's locked. You'd only ever see exactly the same side towards you. Okay, here's a problem. When your orbit is not circular, when it's elliptical, you are moving faster in your orbit when you're closer and slower in your orbit when you're farther away. Okay? So the point is, if you are tidally locked and in a perfectly circular orbit, for every little bit around the Earth you revolve, you will rotate a little bit, always keeping that same face pointed so everything works out. But if you're going a little faster than average or a little slower than average, that little bit that you rotate doesn't line up as it would if you were in a perfectly circular orbit. It lines up on average. But if you're sort of fast in your orbit, then that little bit that you turn doesn't quite compensate for how far you've gone around the Earth. And if you're slow in your orbit, you haven't quite turned enough right. So when you look at time lapse photos of the Moon, it is striking to behold. The Moon is like, it's like turning a little to the left to you, a little to the right. So we can see more than 50% of its surface over the duration of a moonth.

[Chuck Nice]

Okay.

[Neil deGrasse Tyson]

Month. Excuse me?

[Chuck Nice]

A moonth. I like that better. It's the month on a month.

[Neil deGrasse Tyson]

That's the original word, of course, a moonth.

[Chuck Nice]

Yeah. Well, go ahead.

[Neil deGrasse Tyson]

Yeah, yeah, so. And yes, to the extent that there's a wobble and anybody cares about it, that's true. Anytime you have a rotating object where it's not perfectly spherical, if there's a slight bit of mass off to the side, then there are extra torques on it and that'll sort of bob as it turns. We wobble on our axis because of forces that are tugging on us, such as the Moon as we rotate and as we go around the Sun. So you do get this sort of wobbling and bobbing. But for me, the fun thing is the libration. If you just Google libration of the Moon and look at the time lapse video, it's striking. Cause you don't get to see it that way because we see the moon once a night or once a day. And when you time lapse it for.

[Chuck Nice]

A month, that's when it reveals it's kind of like the face that it shows us just turns a little bit.

[Neil deGrasse Tyson]

Yeah, exactly. Thank you. That's way easier. That's what I should have done. It got a little to the left, a little to the right.

[Chuck Nice]

So it's like when it's 25,000 miles out, it's like Le Tigre.

[Neil deGrasse Tyson]

And.

[Chuck Nice]

And when it's, like, right close to us, it's like Blue Steel. So.

[Neil deGrasse Tyson]

If I even know what blue Steel means, that's embarrassing, okay? Not really.

[Chuck Nice]

That's not really embarrassing.

[Neil deGrasse Tyson]

You were in the movie. I was in Zoolander 2.

[Chuck Nice]

That's right. Yes, that's right.

[Neil deGrasse Tyson]

And I did do a Blue Steel imitation. I did. In fact, it's the very final thing you see in the movie. I am the last thing you see in the movie Zoolander 2.

[Chuck Nice]

And anyone listening, please go look at that. No, don't.

[Neil deGrasse Tyson]

Please don't look at that.

[Chuck Nice]

Please go look at that. Because I believe you're wearing a fur coat, too, which is.

[Neil deGrasse Tyson]

No, it's a shoulder wrap.

[Chuck Nice]

Fur.

[Neil deGrasse Tyson]

I don't think it's a full coat. I think it was just something around my upper shoulders and neck.

[Chuck Nice]

Yeah. Like, they call that a stole back in the day.

[Neil deGrasse Tyson]

Stole. It was a stole. Right, right, right. And then I sort of turn my head, and then I make. Give the expression. Just to be clear, Chuck. Okay, okay. I've been in four movie franchises, okay? And for three of them, there were no more movies made after. While I was in.

[Chuck Nice]

That's pretty damn hilarious.

[Neil deGrasse Tyson]

Okay. So I was in Ice Age 5, okay? And the critic said it's about time the series went extinct. Like all the creatures in it.

[Chuck Nice]

Oh, damn. Oh, my God.

[Neil deGrasse Tyson]

I thought it was a pretty good movie, though. Cause it had a lot of science in it. So I was science biased. That's why I was one of the characters. So that was the last of the Ice Ages. I was in Sharknado 6.

[Chuck Nice]

Okay.

[Neil deGrasse Tyson]

You didn't know there were five others, did you?

[Chuck Nice]

Well, I did not. Number one.

[Neil deGrasse Tyson]

Okay?

[Chuck Nice]

And I'm so glad to hear that there's not a Sharknado 7. I'm just saying.

[Neil deGrasse Tyson]

So unlike the Fast and the Furious.

[Chuck Nice]

Could you please be in that? Please be in that?

[Neil deGrasse Tyson]

No, but I don't want to kill the franchise. I do.

[Chuck Nice]

And that's why I want you to.

[Neil deGrasse Tyson]

That's why you want me to be good so that the franchise dies?

[Chuck Nice]

Exactly. I just want the last scene to be you, like, cruising, like, yo, what up? Keep looking up. But not while you're driving.

[Neil deGrasse Tyson]

Not while you're driving. All right, give me another question.

[Chuck Nice]

Okay, here we go. Zach Metcalf wants to know this. Good morning, gentlemen. Have anatomically modern human beings always lived under the same night sky? Have the stars had time to migrate and rearrange themselves in approximately 150,000 years that we've been looking up.

[Neil deGrasse Tyson]

Love that question. So, first of all, the dude knows that however fixed the stars look like they are on the night sky, in fact, they are moving through space. And obviously, the farther away something is, the less from day to day, you're gonna notice that it's moving. Right. So that's true on Earth as well. This is what led to the old childhood concept where you say, mommy, Daddy, why is the moon following me right as you walk down the street? Because the trees go by and the buildings go by, and the moon is just there. Well, if you kept walking for a million more miles, you would leave the moon far behind. So you're just not walking far enough for something that distant to reveal the fact that you're walking past it. So the farther away something is, the less obvious its motion is to you. Okay, cool. So the. So we have all the stars in the night sky, and they are part of the solar neighborhood. How's that for a friendly phrase that we use? It's a solar neighborhood.

[Chuck Nice]

You're now the Rogers of the cosmos.

[Neil deGrasse Tyson]

Welcome to the neighborhood.

[Chuck Nice]

Yes. Hello, neighbor.

[Neil deGrasse Tyson]

Oh, you're about to explode as a supernova. Oh, let me get the hell out of the neighborhood. Okay, that would be an interesting accident. All right, so we're all orbiting sort of the center of the galaxy together. But even with that sort of community movement, there's movement among us. Okay, Right. So if you go back 75,000 years, we were anatomically human 100,000 years ago. You would not recognize most of the constellations of the night sky.

[Chuck Nice]

What?

[Neil deGrasse Tyson]

That's right. That's right.

[Chuck Nice]

Oh, man.

[Neil deGrasse Tyson]

Well, not most. I would say about half the nearby. The stars that are nearby us that trace out the constellations, they'd be in a completely different place. Amazing. So, for example, the Big Dipper, which we know of as looking like in. Where is it in England? Is it called the Big Saucepan? The Big Ladle someplace? The ladle. The ladle is the Little Dipper. The Little Dipper. The handle bends the other way like a ladle would. Okay. And the Big Dipper. Point is, all the stars of the Big Dipper, believe it or not, are part of a coherent star cluster, which is really close. So you don't think of Them as a tight cluster, but so they're all sort of together and they're moving in their own sort of orbits. And. And the Big Dipper would get flattened out. It turns out we've done the math on this.

[Chuck Nice]

Wow.

[Neil deGrasse Tyson]

You just wouldn't recognize it as a Big Dipper at all. Okay, give me some more Teresina.

[Chuck Nice]

No last name like Cher, just Teresina. And Teresina says, hey, Neil. Hey, Chuck. Why is mercury the element? Okay, very nice clarification there, Teresina.

[Neil deGrasse Tyson]

If you're talking to astrophysicists, she gotta express.

[Chuck Nice]

You gotta make that clarification.

[Neil deGrasse Tyson]

Yes.

[Chuck Nice]

She says, why is mercury the element liquid? The elements before and after it in the periodic table. Gold and thallium are both solid at ambient temperature. So why does one proton make such a difference? Ooh. Ooh, I love that question because I have no idea why.

[Neil deGrasse Tyson]

Well, I'll get to that question when we return after our first break on StarTalk. Cosmic queries. You know, Donald, I just want to.

[Chuck Nice]

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[Neil deGrasse Tyson]

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[Reggie]

Reggie, I just sold my car online.

[Neil deGrasse Tyson]

Let's go, grandpa. Wait, you did?

[Reggie]

Yep, on Carvana. Just put in the license plate, answered a few questions, got an offer in minutes. Easier than setting up that new digital picture frame.

[Neil deGrasse Tyson]

You don't say.

[Reggie]

Yeah, they're even picking it up tomorrow. Talk about fast.

[Neil deGrasse Tyson]

Wow. Way to go.

[Reggie]

So about that picture frame. Ah, forget about it. Until Carvana makes one, I'm not interested.

[Angie Hicks]

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[Neil deGrasse Tyson]

Hello, I'm Vinky Brooke Allen and I support StarTalk on Patreon.

[Chuck Nice]

This is StarTalk with Nailed Grass.

[Angie Hicks]

Tyson.

[Neil deGrasse Tyson]

Chuck, we're back. Cosmic Query. Okay, grab bag questions coming from everywhere.

[Chuck Nice]

Yep, that's right.

[Neil deGrasse Tyson]

Left field, right field, behind home plate.

[Chuck Nice]

That's when you know a fan is mad.

[Neil deGrasse Tyson]

Oh, if it comes from behind.

[Chuck Nice]

If it comes from behind.

[Neil deGrasse Tyson]

Well, if they throw at your head, then they're mad at you.

[Chuck Nice]

Yeah, exactly.

[Neil deGrasse Tyson]

So this last question was from Teresina. Who is this.

[Chuck Nice]

Yep, Teresina. Who says. Hey, Neil. Chuck. Why is the mer. Why is mercury the element liquid? The elements before and after in the periodic table are both solid at ambient temperature. So why does one proton make such a difference?

[Neil deGrasse Tyson]

Okay, I can answer that. I don't have a good idea.

[Chuck Nice]

I don't know. Wow.

[Neil deGrasse Tyson]

Okay. Well, I mean, I can fumble through an answer. Okay, I will give you an answer, but it will be wholly unsatisfying because I don't have a deep understanding of it. But I can give you an answer. And here it is. You ready?

[Chuck Nice]

All right.

[Neil deGrasse Tyson]

Okay.

[Chuck Nice]

Because I said so. Because it's nature.

[Neil deGrasse Tyson]

Thank you, Chuck. Next question. Thanks for helping me in.

[Chuck Nice]

That cleared up. Did that clear it up for you? It'.

[Neil deGrasse Tyson]

Crystal clear.

[Chuck Nice]

There you go. All right, go ahead.

[Neil deGrasse Tyson]

So you say, how could only one proton in the nucleus make such a difference? Cause you're comparing what was to the left of it and to the right of it on the periodic table. And the periodic table is an ascension of proton count in the nucleus of atoms. That's what that is. And you go from hydrogen at number one to one proton up to uranium, 92 protons. And then the elements we create in the lab goes up to. I forgot what they're up to now. 120, something like that. So it turns out, remarkably, what we learned from applying quantum physics to the periodic table is that vertically on the table, elements have properties, chemical properties similar to each other. So where you find carbon, for example, you look directly what's directly below it. It's silicon. And so we're carbon based life. So everyone is eagerly looking for silicon based life. If carbon can make life in all these molecules that comprise life as we know it, silicon sitting right below it makes the same families of molecules as carbon does. And so elements in vertical columns. We've learned how and why that's so from. Quantum physics has similar chemical properties, but the melting point is not a chemical property. It's actually intrinsic to the element itself. And so what happens when you change it? Then the charge changes in the nucleus of the atom, and that changes the electron orbitals in response to it. Not orbits, but orbitals, we call them inspired by the orbits of planets. By the way, because we thought maybe you have solar system with the sun in the middle and planets in orbit around it. As we start poking the atom, it's got a nucleus, it's got electrons, maybe it's the same thing, but just little. And it's not. Whole other laws of physics apply there. And it's the realm of quantum physics. So point is, Mercury melts at about 40 degrees below zero, and so it's liquid that all degrees above that until it evaporates. And that's a unique property. So many elements on the periodic table have unique properties relative to everything around them that it's one of the reasons to celebrate that it exists at all. And it's a testament to the genius of chemists and physicists who go into those elements and say, this has this property. So I want to do this other thing with it. This conducts electricity. This does not conduct electricity. This is brittle. This is flexible. This is gaseous. This is liquid. And so we've gone all into the periodic table and basically constructed civilization based on it. So I don't have a good answer for you because I don't know what to tell you about why that's liquid and nothing around it is left or right or up or down. But I can tell you being liquid is not the most. It's not the most different thing about an element that you can find among elements on the periodic table.

[Chuck Nice]

Wow. Okay.

[Neil deGrasse Tyson]

And by the way, if we lived in a world that was 50 below zero.

[Chuck Nice]

Right.

[Neil deGrasse Tyson]

You wouldn't be asking this question. Mercury would be solid like every other element. Okay. We can go to a warmer environment, and you'd find some things that then become liquid. And you might be asking that about those other elements. So the fact that we are okay in these quote, room temperatures has consequences for which elements on the periodic table are solid, liquid, or gas.

[Chuck Nice]

Wow. That's right.

[Neil deGrasse Tyson]

So that's me dancing around the fact that I don't actually know the answer to that question.

[Chuck Nice]

Okay. So for somebody who I'd hate to know. If you knew the answer. God, we'd be here till next year if you actually knew the answer.

[Neil deGrasse Tyson]

What I'll do is I'll do some homework on it, and I'll come back and see what I can tell about the relationship of one mercury atom to another and why it is that at this temperature, unlike every other metal on the periodic table, that they don't make a solid lattice. I'll find out and I'll get back to her.

[Chuck Nice]

All right, well, thanks, Teresina, for giving Dr. Tyson, some homework. All right, let's. Here we go. This is.

[Neil deGrasse Tyson]

Oh, by the way, there's an element, and I forgot which element. Forgive me. I'll dig it up the next time I return. In the uk, the ambient indoor temperature lab temperature is slightly lower than in the United States or in Germany or in France. And so when the UK folks made their periodic table, there's an element that they listed as liquid. But in the United States and France and everywhere else, it was listed as. I'm sorry, listed as solid. But for everybody else, it was liquid.

[Chuck Nice]

Wow. Yeah. So just from a slight variation in the lab.

[Neil deGrasse Tyson]

Yeah, Just because the ambient lab temperature in England is about 5 degrees cooler than the ambient lab temperature in other sort of industrialized states at the time. So the point is, if you want to think of the periodic table as some deep fundamental truth about the universe, then you should not be distracting yourself about whether it's solid, liquid, or gas at your laboratory temperature, because the universe doesn't give a rat's ass about your laboratory temperature. That's not a fundamental truth about the element, whether it's liquid in your lab.

[Chuck Nice]

Yeah, there you go. Don't you know who I am? I'm the universe.

[Neil deGrasse Tyson]

Thank you.

[Chuck Nice]

You want me to think what you're.

[Neil deGrasse Tyson]

What?

[Chuck Nice]

You say, you cold, you need a sweater. I'm the universe.

[Neil deGrasse Tyson]

Are you kidding? That's right. Yeah. So, yeah. So there you think this is cold.

[Chuck Nice]

I'm at an absolute zero. Well, a couple degrees above it all the time.

[Neil deGrasse Tyson]

And you know the methane that comes out of your stove, if you use a gas stove, right. On Earth, that's gaseous, you go to Saturn's moon, Titan, right? It has the right combination of temperature and air pressure to liquefy. Methane.

[Chuck Nice]

Mm. Swimming in methane. Sounds like a dream.

[Neil deGrasse Tyson]

And the water, it is so cold that the water has frozen so solid that it's basically the bedrock on the planet. There are boulders, and it's just ice, but those are the rocks. And think about it. Inside a volcano, what happens to rock?

[Chuck Nice]

It melts. It melts.

[Neil deGrasse Tyson]

So if we're in an environment that's as hot as a volcano, you would not think of rocks as anything solid. You say, oh, that's a liquid. Let's take a bath. And so these conditions that you happen to live in are not themselves fundamental to what's going on on the periodic table.

[Chuck Nice]

Wow. There you go. All right. Terracina. We got more out of that than I ever thought. For somebody who said that, I don't know. Only physicists and astrophysicists answer questions that they don't know for six minutes. All right, here we go. Here we go. This is Jordan Bellaconis. He says, hey, doctor.

[Neil deGrasse Tyson]

Oh, wait, wait, wait. One other thing.

[Chuck Nice]

Okay.

[Neil deGrasse Tyson]

There are places on Mars where the temperature and the air pressure, the atmospheric pressure are just right. That water, if you live there, water would freeze, meltdown, and boil all at the same time.

[Chuck Nice]

What?

[Neil deGrasse Tyson]

So you can have a bowl of water with ice cubes in it and the water is boiling and that's stable.

[Chuck Nice]

That's pretty. Okay, I was gonna say that's hot, but it's not. So it's not.

[Neil deGrasse Tyson]

And I was.

[Chuck Nice]

It's called the trickle point, but it's okay. That's hot and cool, and that's everything.

[Neil deGrasse Tyson]

That's everything at the same time.

[Chuck Nice]

It's not hot.

[Neil deGrasse Tyson]

It's good. It's not tepid. Right. So it's called a triple point. And water has a triple point of atmospheric pressure and temperature where all states, three states of matter can coexist happily. And so, yeah, that's why you can say water is liquid. No, water is only liquid when you make it a liquid. Okay.

[Chuck Nice]

Right.

[Neil deGrasse Tyson]

Otherwise, it's solid or gaseous. All right, cool. There you go. Right.

[Chuck Nice]

All right. Jordan Belacanis. Yep. He says, hey, Dr. Tyson and Chuck, what's happening? I never have been able to understand the thought of terraforming Mars, considering. Listen, here's the real thing. It's a dead planet with no magnetic field. It seems solar wind and extreme UV would strip the atmosphere and kill any life anyway. Can you please help explain how this would ever work?

[Neil deGrasse Tyson]

Okay, so he's two steps ahead of someone who might have only just now heard of terraforming. So terraforming is you take a dead planet and then you seed the atmosphere with aerosols, or you introduce microbes that will thrive on the carbon dioxide and might output oxygen. And then you step back and let it run its thing. If you put in the right cocktail. And then out comes an arable, green planet that you just terraformed. That's not an impossible dream. Okay? It's not. I mean, Earth was terraformed early on by Earth itself. Right. So the question is, can you do it, like, fast? If you have to leave Earth, you gotta find another place to do it.

[Chuck Nice]

They did in one Star Trek movie.

[Neil deGrasse Tyson]

They did in the movie. Yes, yes. It was the Genesis movie.

[Chuck Nice]

The Genesis.

[Neil deGrasse Tyson]

That's what it was called, the Genesis Project. Right. They took some pod or something and sent it down. And I think it was a pod. No, no, no, the pod was somebody's dead body that then came back to life.

[Chuck Nice]

Oh, Spock.

[Neil deGrasse Tyson]

Yes, Spock. Yeah.

[Chuck Nice]

Yeah.

[Neil deGrasse Tyson]

Cool. Okay. So Jordan is worried that because Mars does not have a magnetic field, which would then shield it from solar wind, whose energy can break apart molecules or have ozone that would protect it from ultraviolet, all of these. Without these protections, life on Earth, we don't know how you would sustain it. Okay, that's fine. Consider that if you're living underground, none of that matters.

[Chuck Nice]

Oh, there you go.

[Neil deGrasse Tyson]

Or if you shield yourself from the sun, none of that matters.

[Chuck Nice]

Martian Morlocks. I forgot. Yeah, Martian Morlocks, that's what we got.

[Neil deGrasse Tyson]

So, first of all, you can just shield yourself from it. Second, if we have the power of geoengineering to turn Mars into an arable place, I don't see why we couldn't figure out some way to deflect the solar wind or to block out uv. I'm not worried. That's like an engineering challenge, and engineers tend to solve problems when given the task, and so I'm not worried about that. It's the rest that is way more complex. We know how to block uv. We know how to block the solar wind. We don't know how to send in microbes and come back 10 years later and have a forest. We just don't know how to do that. That's where the challenges are right now.

[Chuck Nice]

Gotcha. Gotcha. So we got the sunscreen covered.

[Neil deGrasse Tyson]

Exactly.

[Chuck Nice]

That part's good.

[Neil deGrasse Tyson]

Yeah, yeah. We good? We good?

[Chuck Nice]

All right.

[Neil deGrasse Tyson]

Okay.

[Chuck Nice]

Well, there you go, Jordan. I mean, at least you're thinking two steps ahead of anybody else.

[Neil deGrasse Tyson]

Who's thinking exactly.

[Chuck Nice]

Terraforming. Good for you. All right, here we go.

[Neil deGrasse Tyson]

Oh, by the way, if you have good geoengineering, you might find a way to stir up the Martian core so that it can then generate another magnetic field. I mean, what's stopping us, right? Yeah. Earth gets its magnetic field from our iron core.

[Chuck Nice]

The iron core that's standing inside of us.

[Neil deGrasse Tyson]

Yeah, yeah. Inside of that has this moving iron, which is conductive. And when you have a conductive moving material, it can generate currents, and currents generate magnetic fields. So Mars, that's all stopped long ago. But why not, if we can control planets, go stir it up again.

[Chuck Nice]

Right? See, Mars, that's why nobody finds you attractive because you have a magnetic field.

[Neil deGrasse Tyson]

Just don't.

[Chuck Nice]

I just made that up. Come on, man.

[Neil deGrasse Tyson]

Okay, all right. You don't have to test it on this program. Go to open mic night and see how people do.

[Chuck Nice]

Damn. Oh, My.

[Neil deGrasse Tyson]

Boy. That was damn comedic dig, though.

[Chuck Nice]

Oh. Oh, my goodness. Damn.

[Neil deGrasse Tyson]

Chuck is wiping away his tears.

[Chuck Nice]

Oh, man. Cause you got me with that one, man.

[Neil deGrasse Tyson]

That's.

[Chuck Nice]

You ain't got to test it out here.

[Neil deGrasse Tyson]

Testing out on my show. Oh, Justin.

[Chuck Nice]

Oh, man, I need some Visine now.

[Neil deGrasse Tyson]

All right, here we go. All right, Chuck, we gotta take a quick break. Oh, okay.

[Chuck Nice]

All right.

[Neil deGrasse Tyson]

We'll come back to segment number three of StarTalk Cosmic Aquarius. Grab that. Be there.

[Reggie]

Reggie. I just sold my car online.

[Neil deGrasse Tyson]

Let's go, Grandpa. Wait, you did?

[Reggie]

Yep. On Carvana. Just put in the license plate, answered a few questions, got an offer in minutes. Easier than setting up that new digital picture frame.

[Neil deGrasse Tyson]

You don't say.

[Reggie]

Yeah, they're even picking it up tomorrow. Talk about fast.

[Neil deGrasse Tyson]

Wow. Way to go.

[Reggie]

So, about that picture frame. Ah, forget about it. Until Carvana makes one, I'm not interested.

[Angie Hicks]

Car selling made easy on Carvana.

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[Neil deGrasse Tyson]

All right, we're back. StarTalk Cosmic Query. Chuck. You're tweeting at Chuck. Nice comic.

[Chuck Nice]

Yes, thank you, sir.

[Neil deGrasse Tyson]

I do indeed follow you. I don't follow many things. I follow you. Just let you know.

[Chuck Nice]

Well, that's great. I followed you first, so it's not a competition.

[Neil deGrasse Tyson]

I can't top that. Sorry.

[Chuck Nice]

There you go.

[Neil deGrasse Tyson]

All right, what are the questions you got for us? We have one segment left. Let's see how Many we can squeeze in.

[Chuck Nice]

Let's see what we can do here. This is abhinav yadav. Hello, Dr. Tyson and sir. Nice. I'm excited to be asking my very first question. Now, you have spoken about Moon disrupting observation time.

[Neil deGrasse Tyson]

Oh, yeah.

[Chuck Nice]

Are there places in the solar system that are much better for it where this doesn't exist? Somewhere we can just send telescopes and observe? Love the show.

[Neil deGrasse Tyson]

Yeah, there's a lot going on in that question. So let me just unpack it briefly. So first of all, the full moon at night is crazy bright, right? In fact, it's something like six times brighter than a half moon. Because of the way the laws of reflection work. You think it'd only be like twice as bright. It's like even brighter. So on a moonless night, the unaided eye can see a couple of thousand stars. If the Moon is out, you can see a couple hundred stars. So it drops it by a factor of 10. So if you're trying to see the deep universe, we have what's called dark time at telescopes. And it's highly competitive to gain access to a telescope while the Moon is not up. Okay. It's called dark time. And people who are on the brink of the detection of things will ask for dark time. So then we learned, well, why be on Earth at all? Why? Okay, but if you go into orbit, the Moon is still there, okay? Now, the sky is not as bright, but it's still kind of. You don't wanna look near the Moon. You have scattered light into your telescope beam. So how about a million miles on the other side of the Moon? How about that? Well, that's where the James Webb Space Telescope is going.

[Chuck Nice]

Oh, cool.

[Neil deGrasse Tyson]

Ooh. Yeah. So it's far away from Earth and from the Moon. And so, yeah, we're doing our darndest to get rid of the interference that we're now experiencing. But let me stay at it. There's radio interference and we have radio wave telescopes.

[Chuck Nice]

Right.

[Neil deGrasse Tyson]

So what are we gonna do about that? There's all this talk whole conference has given unto putting radio telescopes on the far side of the moon. Wow. Because the Moon only shows one face. So if you're on the far side, you will never see Earth, ever.

[Chuck Nice]

Right.

[Neil deGrasse Tyson]

Okay. So that famous photo of Earthrise over the moon by Apollo 8. Okay. Earth doesn't rise on the Moon, right? It never does. It's either always there or never there because you're either on the side of the Moon that faces Earth or the side of the Moon that faces elsewhere. And so the Reason why that's called Earthrise is cause they were orbiting the moon, right? When you're orbiting, then the sky rises and sets. And so they caught the rising Earth on the lunar landscape. So it's, it's legitimately Earth rising. It's just highly misleading. Right, that's all.

[Chuck Nice]

It's like moon Haiti and moon Dominican Republic. So just same island, just one side is Haiti and the other side Republic.

[Neil deGrasse Tyson]

Is that really the first. I'm talking the universe here and you're talking geopolitics.

[Chuck Nice]

Man, I need a vacation. I'm really just thinking about tropical places. Is that.

[Neil deGrasse Tyson]

That's right. But they are the same island. Somebody just cut a line right down the middle. Cut a line.

[Chuck Nice]

That's it.

[Neil deGrasse Tyson]

Right. Well, so, yeah, so we are thinking about that and it is a big problem. And so wherever the electromagnetic spectrum is noisiest, we try to do our darndest to avoid it. And sometimes it means going into space, to the far side of the moon, and even into deep space itself.

[Chuck Nice]

Wow, cool, man.

[Neil deGrasse Tyson]

Yeah, yeah.

[Chuck Nice]

All right, so okay, now what. What probe just got out of our solar system. And will we be able to receive. So I'm just thinking about telescopes.

[Neil deGrasse Tyson]

Oh, you talk about Voyager. Voyager, yeah.

[Chuck Nice]

So will we be able to get, retrieve any information from that ever?

[Neil deGrasse Tyson]

In principle. But the cost of maintaining that, relative to other things, we have what's called a senior review of projects that are growing long of tooth, that have been going for a while. Even if they're giving trickles of data, you say to yourself, it costs this much. What is the incremental knowledge we're gleaning about our state of the universe relative to this new project that is looking for seed funding to discover something new and exciting. And so sometimes you got to turn off the switch. Voyager, we turn off the switch after it exited the influence of the sun. There's everyone thinking, oh, the solar system ends at Pluto. No, no, the solar system keeps going. And one way to think about it is as long as you're near enough to the sun to feel its sort of magnetic field and other effects, you say, I'm part of the solar system, but the galaxy has a magnetic field also. So if you start getting farther and farther away from the sun, the strength of the sun's magnetic field drops. And the strength relative to the strength of the galactic magnetic field, you reach a point, oh, by the way, it's not just magnetic field, but the particle stream emanating from the sun relative to the ambient particle stream in the galaxy, you reach a Point where you can no longer tell the difference between those two. Bada bing, You've left the solar system. Cool. Yeah. All right. That's how you think about that?

[Chuck Nice]

All right. That's how you think about it?

[Neil deGrasse Tyson]

All right, cool. That's how we roll it.

[Chuck Nice]

And since we're talking telescopes here, when you talk about observation time earlier.

[Neil deGrasse Tyson]

Mm.

[Chuck Nice]

If you're an important.

[Neil deGrasse Tyson]

Well, are you asking a question now?

[Chuck Nice]

No, this is, you know, this is still abhinav.

[Neil deGrasse Tyson]

Yeah. Okay. I was just, you know. Cause you gotta become a Patreon member if you're gonna ask me a question. That's all. I'm just checking. Go on. Because you. You got all the data there, so.

[Chuck Nice]

Yeah, I also. I'm also lying. But, hey, No, here's what I wanna know. If you're an important scientists, do you get bumped up in your request for observation time? Are they just like, jimmy, please. You're really that research. Get out of here.

[Neil deGrasse Tyson]

Yeah. Your seniority has nothing to do with it. It's how brilliant is your idea. And that's why on our research papers, we don't put your earned degrees next to your name. All right, so an undergraduate, one of these sort of precocious research interested graduate students could have their name right next to someone who's highly senior or even a Nobel laureate. No degrees are put there. No such distinctions are made.

[Chuck Nice]

Oh, my God, it's the mast physicist. I love it. Instead of the math singer. The math physicist.

[Neil deGrasse Tyson]

Yeah. So we don't. And I think that's one of the. That's an important feature of the entire enterprise. Now, if you have an idea that's a little crazy that it's not getting past any reviews, the director of the telescope has what's called director's discretionary time. And they can say, you know, I want to give this a shot.

[Chuck Nice]

Oh, wow.

[Neil deGrasse Tyson]

And they can grant the time and it won't have to go through the peer review to be given the time. Oh. But ultimately, the research you do based on it would have to be peer reviewed if you're going to publish it. Okay.

[Chuck Nice]

That's a great system, by the way.

[Neil deGrasse Tyson]

It is. It is. And by the way, the very famous Hubble Deep Field. Do you know that picture that has just galaxies in it?

[Chuck Nice]

It's beautiful.

[Neil deGrasse Tyson]

And there's a couple of stars. But everything you might think is a star is an entire galaxy that was allocated on director's discretionary time.

[Chuck Nice]

Okay.

[Neil deGrasse Tyson]

And it became one of the most significant images ever taken by the telescope. And you know who received that Discretionary. That director's discretionary time.

[Chuck Nice]

No.

[Neil deGrasse Tyson]

Who? The director gave it to himself. No.

[Chuck Nice]

Yes. Get out.

[Reggie]

Yes.

[Chuck Nice]

Oh, that's tremendous. Yes. Is that badass? He was like, you know what, man?

[Neil deGrasse Tyson]

That's gangster.

[Chuck Nice]

You know, I want to look out into nothing, and there's nothing.

[Neil deGrasse Tyson]

You could. You can't stop it.

[Chuck Nice]

Why would you point the telescope that way? There's nothing there. Because I can. All right? I'm the director. I'm the hdi. I see the head director in charge, Bjarch.

[Neil deGrasse Tyson]

Okay, so the funny thing is, you're absolutely right. The Hubble Deep Field was a spot on the sky. That was the least interesting spot you can possibly find. There were no interesting stars, no previously discovered interesting galaxies, black holes, nothing. And he says, let me take the most potent, powerful telescope in the world and aim it. There's. And hang there and let those meager photons accumulate, and let's see what's lurking in the dark. Thus was born the Hubble Deep Field. It may have been the most significant image taken by the telescope itself. And so we allow for that kind of creative thinking that might not otherwise get through.

[Chuck Nice]

By the way, what a great story I'm telling.

[Neil deGrasse Tyson]

I love my people. These are my people.

[Chuck Nice]

I mean, seriously, that's probably equally as exciting as the discovery itself. All right, this is Dale Buen, and Dale says, hey, Neil. Photons don't experience time. They don't ever decay. Would they decay? Wait a minute. Would they decay if they did experience time?

[Neil deGrasse Tyson]

Yeah. So decay means you are this. This form of matter in one moment, and later on you're a different form of matter. And you can time that out, and there's usually some variance there, but there's a very tight average that we give for, like, it's called the half life. For example, carbon 14. Any radioactive element has a half life. Well, if all the atoms know that they're supposed to convert within some statistical time frame, then they must have a measure of time. There must be some kind of clock going on within them. All right? Photons moving at the speed of light, time stops for them. So if you have no measure of time, then you cannot know to turn into anything else later in life, because there is no later. If photons did happen to experience time, it means they would not be going at the speed of light. Okay. And they would not be pure energy as they currently are. And then they would have the ability to transform into another kind of particle.

[Chuck Nice]

Wow.

[Neil deGrasse Tyson]

Yeah.

[Chuck Nice]

That is so trippy, man. Oh, my God. That is so trippy. Okay.

[Neil deGrasse Tyson]

Because they would know how to keep time. And if you know how to keep time, you would have some clock. And you say, you know, in one year, five years, three seconds, a tenth of a second, I'm going to turn into another particle. Now, just because you have a clock doesn't mean you will turn into another particle. The other conditions have to be right. But if you don't have a clock, there's no reason or understanding we possibly have for why you would change into another.

[Chuck Nice]

Okay, so photons are super gangster.

[Neil deGrasse Tyson]

So it means the photon that we detect here that was emitted in the early universe shortly after the Big Bang, as far as it's concerned, it's still a big bang.

[Chuck Nice]

Hey, let me tell you something, man. I'm a photon. I don't ride or die. I ride and die. I take the ride.

[Neil deGrasse Tyson]

Always dying and always living at the same time. So it is detected in the same instant that it is emitted.

[Chuck Nice]

Right.

[Neil deGrasse Tyson]

According to the photon itself. So that's fascinating. So life as a photon, like you said, it's a trippy thing.

[Chuck Nice]

Wow.

[Neil deGrasse Tyson]

Yeah.

[Chuck Nice]

God, I love science.

[Neil deGrasse Tyson]

Yeah.

[Chuck Nice]

I mean, that is just amazing. Okay, let's get another one in here.

[Neil deGrasse Tyson]

Maybe we can slip in another one. Yeah.

[Chuck Nice]

Okay. This is Nicholas Lenson. Nicholas says, hey, Neil. Hey, Chuck. Given that the black holes lose mass slowly but thoroughly until they no longer exist, would there be a point in time where the mass of the black hole is no longer sufficient to trap light? So the surface of the black hole would become visible? And what would that look like? So wait a minute. Did this guy just discover a way to look inside of a black hole?

[Neil deGrasse Tyson]

In principle. So it turns out that any amount of mass you can calculate how small it would have to be, how compressed it would have to be for it to become a black hole. So if you wanted Earth to become a black hole, you'd have to shrink it down to, like, the size of a plum. Last I did the math on that. So if you manage to do that, bada bing, you have an Earth black hole. The point is a lower mass black hole is smaller than a higher mass black hole. If a black hole begins losing mass, it gets smaller and becomes the black hole size appropriate for the amount of mass it has. So it's stuck being a black hole.

[Chuck Nice]

It's always gonna be a black hole.

[Neil deGrasse Tyson]

Correct.

[Chuck Nice]

No matter what the mass is. Now that it has collapsed into a black hole, it can't be anything else.

[Neil deGrasse Tyson]

Correct.

[Chuck Nice]

So if it continues to lose that mass, it will always maintain the properties of a black hole because it can't.

[Neil deGrasse Tyson]

Be anything else as it shrinks down. That's right. Now, if for some magic force of nature, the black hole evaporates, according to Hawking radiation, which your guy clearly knows about, and somehow did not get smaller, there would be a point where the density would no longer allow it to be a black hole. Cause it's about the density. It's not about the mass. The density would know. And then the black hole would slowly reveal itself as a solid object. So, yeah, it was a great question. And if one day we can manipulate the laws of physics, then we could reach into a black hole, somehow prop up its shape so that as it got less and less mass, the density would drop, and then we could reveal what's inside. But then at that point, you're no longer looking inside a black hole, are you? You're just looking at a regular object, right? Yeah.

[Chuck Nice]

Right. Because you really need that mass down to that small density in order for it to be.

[Neil deGrasse Tyson]

And you know what happens as the black hole continues to evaporate? The energy range that gets emitted becomes higher and higher and higher. So large black holes are emitting, like, radio waves, and smaller black holes will emit visible light. The tiniest of black holes will emit gamma rays. Okay. And it has to do with the size of the black hole, whether the wave that it emits can fit inside the black hole or not. That's the quantum physics of it. Hawking worked all this out. Point is, as it gets smaller and smaller and smaller and smaller. The very last bit. Oh, by the way, as it gets smaller, the rate at which it gives off energy increases, okay? So this becomes a runaway process where it gets smaller and smaller, faster and faster and faster. And the very last moment, it happens catastrophically, and you get a little burst of gamma rays. So the original Hawking radiation paper prompted people to look for little bursts of gamma rays, like, in the universe, which could signal black holes dying, having completely evaporated.

[Chuck Nice]

That is amazing.

[Neil deGrasse Tyson]

Yeah.

[Chuck Nice]

Okay.

[Neil deGrasse Tyson]

Now, we do see bursts of gamma rays, but they don't match the spectrum of a dying black hole. But there it is. This is our universe we all live in. It's a beautiful place. Chuck, we're out of time.

[Chuck Nice]

Oh, man.

[Neil deGrasse Tyson]

Darn it.

[Chuck Nice]

Heard it. Darn it.

[Neil deGrasse Tyson]

All right, all right, Chuck. That was fun. So this is another Star Talk. Cosmic queries. Just questions from Patreon members. It was a grab bag. And I want to go back to galactic gumbo because I want to hear you imitate the.

[Chuck Nice]

Put it together guarantee.

[Neil deGrasse Tyson]

I missed that. We can't call it grab bag. We'll figure it out on the next time out. All right, dude, good to have you. Always.

[Chuck Nice]

Always a pleasure.

[Neil deGrasse Tyson]

All right, this has been stark cosmic queries as always. Neil DeGrasse Tyson here bidding you to keep looking up.

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