Bug Splat Galaxies with Mordecai-Mark Mac Low

Summary

StarTalk Radio – “Bug Splat Galaxies with Mordecai-Mark Mac Low”

Host: Neil deGrasse Tyson

Guest: Mordecai-Mark Mac Low (Astrophysicist)

Comic Co-Host: Negin Farsad

Release Date: June 30, 2026

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Episode Overview

This episode of StarTalk’s "Cosmic Queries" dives deep into the wonderfully chaotic universe, focusing on galaxy collisions (the so-called “bug splat” galaxies), the formation of planets and stars, and the power of computer simulations for unveiling cosmic mysteries. Neil deGrasse Tyson and comedian Negin Farsad are joined by astrophysicist Mordecai-Mark Mac Low, who shares insights from simulating the cosmos, recent research on planets forming around black holes, and the surprising order behind the universe’s apparent chaos.

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Key Discussion Points & Insights

1. The Power of Simulation in Modern Astrophysics

[03:00]

• Mac Low’s Role: Describes himself as a “simulator,” using computer programs to model astrophysical phenomena too complex for analytic math.
  • “When things get hairy, we pull out a computer.” – Mac Low [04:21]
• Importance of simulations for understanding galaxy evolution, star and planet formation.
• Early galaxy collision simulations started pre-computers: analog experiments with lamps/photodetectors mimicking gravity.
• Computers have since revealed stages of galaxy collisions and how odd “bug splat” galaxies arise.

2. Bug Splat Galaxies & Colliding Galaxies

[05:00]

• Halton Arp’s Atlas: Catalogued peculiar, “wrecked” galaxies.
• Holmberg’s Lamp Analogy: Early analog models replicated galaxy “splats” and tidal tails; computers later refined the picture.
• Collisions:
  • Analogy: Tyson compares colliding galaxies to marshmallows sticking together—gas clouds crash, stars mostly pass by.
    • “If there were four bumblebees in the continental United States flying randomly, there's a greater chance that two of them will accidentally bump into each other than two stars will collide in galaxies.” – Tyson [08:16]
  • These encounters transform spiral galaxies into massive, smooth elliptical ones.
  • Every galaxy has undergone collisions—this is fundamental to their evolution.

3. Active Galactic Nuclei (AGNs) and Quasars

[09:55]

• Black holes power AGNs, the brightest objects in the universe.
  • “Because black holes are the brightest objects in the universe.” – Mac Low [10:16]
• Brightness comes not from the black hole, but from gas heating up as it falls in, emitting energy across the spectrum, especially X-rays and gamma rays.
• The Milky Way’s central black hole is relatively quiescent now, but evidence shows it was more “active” a few million years ago.
• Our black hole is a “million solar mass” lightweight; brightest quasars reach “a billion solar masses.”

4. Planet Formation Around Black Holes – New Research

[18:18]

• Mac Low recently published research (“Breaking News!” [21:46]) on planet formation in the disks of supermassive black holes.
  • In such massive, dust-rich disks, not just a few but millions of planets can form—some rocky, Jupiter-sized “monsters.”
  • Planets here experience extreme gravity; potential for life is “rather worse” due to intense X-rays & gamma rays from the energetic disk.
    • “There’s a home center of the accretion disk glowing in X rays and gamma rays. It will provide plenty of energy, but it might not be in a form conducive to life as we know it...” – Mac Low [24:11]

5. Nature of Dust, Rubble, and Planetary “Sandcastles”

[25:53]

• Dust grains stick together but are also prone to breaking apart—a tension central to planet formation theory.
• Asteroids are “sandcastles” in space—fragile aggregates, as seen in real events like Comet Shoemaker-Levy 9’s breakup near Jupiter.

6. Star Formation and Cosmic Feedback

[31:00]

• Listener question: How do turbulence and magnetic fields affect star formation?
• Supersonic turbulence stirs clouds, which both facilitates and prevents star formation:
  • “The more turbulence you have, the less star formation you have.” – Mac Low [32:01]
• Magnetic fields are generated by cosmic “dynamos”—rotating, charged gas—requiring turbulence. Stellar birth is thus regulated by a balance of pressure, turbulence, and magnetism.

7. Science as Process – The Value of Skepticism & Data

[33:13]

• “Models have approximations”—science advances by arguing interpretations, then testing against observations:
  • “We will settle our arguments ultimately by reference to reproducible experiments and observations.” – Mac Low [35:22]
• Nature, not personality, is the ultimate judge.

8. Dark Matter in Simulations

[44:28]

• Dark matter is simulated by “sprinkling in” mass particles only affected by gravity, or by assigning gravitational fields in models.
• Distribution: Not uniform—forms the “cosmic web”: clusters, filaments, and voids (the last are “the Wyoming of the universe”).

9. The Origins of Moons and the Rarity of Our Own

[51:06]

• Forming large moons (like Earth’s) in simulations is challenging with current computer power; our setup appears rare.

10. The Universe: Chaotic Yet Governed by Simple Laws

[55:42 & 57:40]

• The universe is not the serene clockwork once assumed, but a turbulent, violent, and astonishingly strange place.
• Key insight: The apparent chaos of galaxies, stars, and planets arises from a handful of physical laws:
  • “But the real majesty is that it’s just a few laws of physics that generate all that chaos.” – Tyson [58:01]

11. Quantum Computing & Future of Simulation

[59:41]

• Mac Low: Uncertain but optimistic—quantum computing may help solve especially complex atomic and molecular processes, but application to astrophysical modeling is likely decades away.

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Notable Quotes & Memorable Moments

• “I'm a simulator.” – Mordecai Mark Mac Low [03:52]
• “Every galaxy in the universe has collided with other galaxies. That's how galaxies are made.” – Mac Low [07:06]
• “The stars just go by each other. Maybe they tug each other a little gravitationally, but basically, they're not gonna run into each other.” – Mac Low [07:56]
• “If there were four bumblebees in the continental United States... greater chance that two of them will accidentally bump into each other than two stars...” – Tyson [08:16]
• “So bug splats turn into beautiful elliptical galaxies... they're disk galaxies that get completely blenderized.” – Mac Low [07:06]
• “Black holes are the brightest objects in the universe.” – Mac Low [10:16]
• “Space is like angeringly huge.” – Farsad [15:39]
• “If you want to get brighter, eat more—like a quasar.” – Mac Low [20:19]
• “Asteroids are rubble piles, but it's really a sandcastle.” – Mac Low [26:01]
• “The more turbulence you have, the less star formation you have.” – Mac Low [32:01]
• “We will settle our arguments ultimately by reference to reproducible experiments and observations.” – Mac Low [35:22]
• “Only 1/6th of the mass of the galaxy is in anything visible... 85% of the gravity is from dark matter.” – Mac Low [47:08]
• “The universe is far stranger than we once thought, and far stranger possibly than we can imagine.” – Mac Low [55:42]
• “It’s just a few laws of physics that generate all that chaos.” – Tyson [58:01]

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Important Segments & Timestamps

• Simulating galaxies & “bug splats”: [04:00–07:06]
• Colliding galaxies & “marshmallows” analogy: [08:00–09:00]
• Active galactic nuclei (AGN)/quasars explained: [09:55–14:00]
• Planet formation in supermassive black hole disks: [18:18–24:11]
• Asteroid/comet “sandcastle” analogy: [25:53–30:09]
• Turbulence, magnetic fields, star formation – listener Q: [31:00–37:26]
• Science as iterative process: [33:13–35:41]
• Simulating dark matter: [44:28–47:20]
• Moon origins & planetary systems: [51:06–54:23]
• Order from chaos – simple laws, wild universe: [55:42–58:01]
• Quantum computing & cosmic simulation: [59:41–60:45]

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Tone & Highlights

• Conversational, nerdy, playful: Frequent jokes about food (“pizza disks” for accretion disks; “sandcastle”-like asteroids), pop-culture asides, and analogies (marshmallows, bumblebees, sponges vs. cosmic webs).
• Explanations are approachable, yet technically robust:
• Strong theme: Science as an evolving process, thriving on questioning, simulation, direct comparison with data, and the willingness to be proven wrong.

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Summary Takeaway

The universe is messy, turbulent, and full of spectacular collisions, but beneath it all lies a remarkable simplicity. Simulations are the 21st-century telescope, allowing astrophysicists like Mac Low to not just observe but rewind, replay, and predict cosmic evolution. From million-planet systems around black holes to the sandcastle fragility of asteroids and the dominance of dark matter, the episode is a celebration of curiosity and the ever-advancing frontier of understanding.

Final thought:
“Keep looking up.” – Neil deGrasse Tyson [62:23]

Transcript

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[Neil deGrasse Tyson]

Ryan Reynolds here from Mint Mobile. I don't know if you knew this, but anyone can get the same Premium Wireless for $15 a month plan that I've been enjoying. It's not just for celebrities. So do like I did and have one of your assistant's assistants switch you to Mint Mobile today. I'm told it's super easy to [e-mail]

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[Neil deGrasse Tyson]

we learned all about colliding galaxies and the formation of planets.

[Comedian/Co-host]

I had no idea how much banging and colliding and smashing there was in this universe all the time.

[Neil deGrasse Tyson]

Coming right up on StarTalk. Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk. Neil DeGrasse Tyson here, your personal astrophysicist. This is gonna be cosmic queries on the formation of planets in the universe. I got with me my co host, Nagin Fassad.

[Comedian/Co-host]

Oh my God.

[Commercial Narrator]

Hello.

[Neil deGrasse Tyson]

Welcome back.

[Comedian/Co-host]

I'm so excited. I've like peeped at some of these questions and they are.

[Neil deGrasse Tyson]

Well, yeah.

[Comedian/Co-host]

Cause they're already querylicious.

[Neil deGrasse Tyson]

Ooh, querylicious. I love that. Very. And just a reminder, you still have your fake the Nation podcast.

[Comedian/Co-host]

That's right. Every week.

[Neil deGrasse Tyson]

Every week. And it's a delight anytime I hear you on. Wait, wait, don't tell me.

[Disney Vacation Club Announcer]

Thank you.

[Neil deGrasse Tyson]

That's the npr, right? Yeah, it's an NPR mainstay.

[Comedian/Co-host]

An NPR mainstay. I've got a lot of tote bags to prove it and we have a good time.

[Neil deGrasse Tyson]

All right. Let me introduce you to my guest today. He's a longtime friend and colleague, Mordecai Mark McLow. Mordecai.

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, hello, Neil. It's weird to me, it's only been 37 years that we've known each other. Yeah.

[Neil deGrasse Tyson]

So I Mean, we came up together, you know, through graduate school. Not at the same graduate school, but we're about the same generation. And he's one of the earliest hires into our brand new department of Astrophysics.

[Mordecai Mark McLow (Astrophysicist Guest)]

Number one.

[Neil deGrasse Tyson]

Oh, you were the number one hire.

[Mordecai Mark McLow (Astrophysicist Guest)]

I am number one into the way to say it.

[Comedian/Co-host]

Is that a way of saying that he's better than you?

[Disney Vacation Club Announcer]

You?

[Mordecai Mark McLow (Astrophysicist Guest)]

No.

[Comedian/Co-host]

Is that what I mean?

[Mordecai Mark McLow (Astrophysicist Guest)]

He under founded the department.

[Comedian/Co-host]

Oh, got you.

[Mordecai Mark McLow (Astrophysicist Guest)]

I was his number one hire.

[Comedian/Co-host]

Okay, you're just better than everyone else here. But.

[Mordecai Mark McLow (Astrophysicist Guest)]

But Neil is still better than you.

[Commercial Narrator]

Got it.

[Mordecai Mark McLow (Astrophysicist Guest)]

There you go.

[Neil deGrasse Tyson]

Number one means he was hired first. Not that he's the number one guy. We're all number one here.

[Disney Vacation Club Announcer]

No.

[Neil deGrasse Tyson]

And what was a delight in your research profile is that you just need a powerful computer and the universe succumbs to you.

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, it's a good sandbox.

[Neil deGrasse Tyson]

Tell me what you do. Because most people's stereotype of the astronomer, astrophysicist, we're at the telescope. Or maybe we're crunching numbers on. Not numbers, but we're on a theorist's notepad. And you are in the middle of that.

[Mordecai Mark McLow (Astrophysicist Guest)]

I'm a simulator.

[Neil deGrasse Tyson]

Simulator.

[Mordecai Mark McLow (Astrophysicist Guest)]

So I do. I run computer programs that.

[Neil deGrasse Tyson]

That you write.

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, that I and my colleagues write. Yes, that. That describe how parts of the universe behave using mathematical equations derived by theorists, but using the computer to derive consequences that would be absolutely impossible to do with pencil and paper mathematics. So when things get hairy, we pull out a computer.

[Capella University Announcer]

Mm.

[Comedian/Co-host]

Do you ever, like, use your powers of simulation for, like, you know, a vision of a grilled cheese sandwich? Or is it mostly just like, space?

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, I would say that I may not do the grilled cheese sandwiches, but there is a simulator somewhere who does.

[Comedian/Co-host]

Okay, I'm sure.

[Disney Vacation Club Announcer]

Okay.

[Mordecai Mark McLow (Astrophysicist Guest)]

And they probably work for Kraft or something.

[Comedian/Co-host]

And they should be your next guest.

[Mordecai Mark McLow (Astrophysicist Guest)]

There you go.

[Neil deGrasse Tyson]

So, Mordecai, I remember when we were coming up, there was a catalog of galaxies, peculiar galaxies, in fact. It was called the Atlas of Peculiar Galaxies.

[Mordecai Mark McLow (Astrophysicist Guest)]

Arp.

[Neil deGrasse Tyson]

Yeah, Halton Arp. And we all scratched our heads wondering, how would nature make objects that looked like this?

[Mordecai Mark McLow (Astrophysicist Guest)]

Like bug splats?

[Neil deGrasse Tyson]

Yeah. The galaxies are just. What? What? And I think in our lifetime, bringing computers to bear on that problem, we would fully understand how you get a disturbed looking galaxy.

[Mordecai Mark McLow (Astrophysicist Guest)]

So that's actually an interesting story because the very first simulation that was done of colliding galaxies that made a bug splat and reproduced these peculiar observations was done in the 1940s, yet using lamps and photo detectors. And as an analog computer cause the lamps simulated gravity because light drops off in intensity just like gravity does. And that actually revealed the basic picture that you get. These splats, these tidal tails, we call them. But then we came along and refined that insight with actual computers. Yes. But the first one was those photo detectors.

[Neil deGrasse Tyson]

Interesting. That wouldn't be Holmberg, was it?

[Mordecai Mark McLow (Astrophysicist Guest)]

I think it was Holmberg.

[Neil deGrasse Tyson]

Yeah, you're right. I remember that.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes.

[Neil deGrasse Tyson]

Yeah. So you've written about this, but I was just a triumph of the simulation modeling universe.

[Mordecai Mark McLow (Astrophysicist Guest)]

Absolutely.

[Neil deGrasse Tyson]

Where so there was a famous astronomer in the day, he would say, alexis, that's wrecked in an accident is not a different kind of Lexus. It's just a wrecked Lexus. And so a wrecked galaxy could have been a perfectly nice galaxy, but then it collided with another galaxy. And with your computer, you can check what it looks like at every step.

[Mordecai Mark McLow (Astrophysicist Guest)]

That's correct.

[Neil deGrasse Tyson]

And then look at the universe and

[Mordecai Mark McLow (Astrophysicist Guest)]

find those steps, all of those steps

[Neil deGrasse Tyson]

being taken by colliding galaxies.

[Mordecai Mark McLow (Astrophysicist Guest)]

And that's how we learned that bug splats turn into beautiful elliptical galaxies. Smooth, uniform, homogeneous. Because they get complete. They're disk galaxies that get completely blenderized. And that's the origin of the elliptical galaxies. Furthermore, every galaxy in the universe has collided with other galaxies. That's how galaxies are made.

[Comedian/Co-host]

Wait, so is it that, like, when two galaxies collide, is it sort of,

[Neil deGrasse Tyson]

like, say it more romantic, when two galaxies collide?

[Comedian/Co-host]

When two galaxies collide come together, but when that happens, is it that, like, they're at a stop sign and neither of them is willing to go, so then they just smash into each other?

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, it's like this. Galaxies are made of stars and gas and dark matter. And stars are very widely separated from each other. So the stars just go by each other. Maybe they tug each other a little gravitationally, but basically, they're not gonna run into each other.

[Neil deGrasse Tyson]

If there were four bumblebees in the continental United States flying randomly, there's a greater chance that two of them will accidentally bump into each other than two stars will collide in galaxies.

[Mordecai Mark McLow (Astrophysicist Guest)]

That's about right.

[Comedian/Co-host]

I'm hearing there's a lot of space.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes, that's right.

[Comedian/Co-host]

Is that what we're doing? Okay, got it. Got it.

[Mordecai Mark McLow (Astrophysicist Guest)]

However, gas is space filling. And so the gas runs into each other and lights up huge shock waves, dust clouds running into each other, new stars forming. All that goes on during the collision.

[Neil deGrasse Tyson]

I got a good analogy for colliding gas clouds. Two hot marshmallows. When they hit, they're stuck. Have you done this? You look at me like, what is he talking about?

[Mordecai Mark McLow (Astrophysicist Guest)]

I mean, I am, too.

[Comedian/Co-host]

Have you, like, roasted marshmallows and then throw them at each other like. I have.

[Mordecai Mark McLow (Astrophysicist Guest)]

I don't know what kind of camping trips you went on. We ate the marshmallows.

[Comedian/Co-host]

He's looking at us like we're the weird ones.

[Disney Vacation Club Announcer]

Okay, so.

[Comedian/Co-host]

No, but I like this. So they don't. They. They stick together and then that's it. They become one marshmallow.

[Neil deGrasse Tyson]

They become, like one marshmallow. And there's an edge between them and everything. So I'm bringing this up just as.

[Mordecai Mark McLow (Astrophysicist Guest)]

But they don't emit X rays.

[Neil deGrasse Tyson]

No, they don't, last I checked. So I'm bringing this up just as a triumph of the bringing numerical simulations to understanding the universe. And you've made a career of doing just that. One of the. Another great mysteries that we had to figure out was galaxies that had weird things going on in their centers, and they give off a lot of energy and a lot of different wavelengths. And we came up with the unpoetic

[Mordecai Mark McLow (Astrophysicist Guest)]

name, active galactic nuclei, or quasars, for the brightest ones.

[Neil deGrasse Tyson]

Especially of late, this has been a big part of your. Your objects of affection.

[Mordecai Mark McLow (Astrophysicist Guest)]

It's one strand of my research, yes.

[Neil deGrasse Tyson]

Oh, just one strand.

[Mordecai Mark McLow (Astrophysicist Guest)]

Just one strand, yeah.

[Neil deGrasse Tyson]

And so tell me about AGNs. What's the latest on them? Do they all have black holes?

[Mordecai Mark McLow (Astrophysicist Guest)]

They all have black holes. That's what makes them so bright. Because black holes are the brightest objects in the universe.

[Neil deGrasse Tyson]

This is where you come in and say, how could a black hole be bright?

[Comedian/Co-host]

Yeah, how could a black hole be bright? I don't understand.

[Mordecai Mark McLow (Astrophysicist Guest)]

Thank you for asking.

[Comedian/Co-host]

And is there a way for the black hole in my soul to brighten up as well?

[Neil deGrasse Tyson]

Yes.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes, there is. Eat a lot, because that's how black holes get bright. So you have gas. And we have already established that if you squeeze gas enough, it gets really, really hot. And if it's really, really hot, it emits a lot of radiation as the fourth power of the temperature. And so what is better at squeezing things than a almost extremely tiny, extremely massive object like a black hole? So you have a black hole in gas, and particularly in the centers of galaxies, there's a lot of gas because it all gets swept into the center as you wish the vacuum cleaner would do. But anyway, so here it is, all this gas falling onto the black hole, and there's not room for all that gas to fall. So it gets squeezed and squeezed and squeezed until it reaches a billion degrees Fahrenheit. And

[Neil deGrasse Tyson]

I was gonna clarify Fahrenheit or Celsius.

[Comedian/Co-host]

Yeah, no, thank God. Okay, okay. Of course.

[Mordecai Mark McLow (Astrophysicist Guest)]

So when it's that hot, it's emitting in the X rays and the ultraviolet and all that light is coming out and that. A lot of it gets converted down into the visible by running into dust clouds and stuff on that.

[Neil deGrasse Tyson]

If you have an electric stove, when it's off, it just emitting in the infrared. Yeah, just mildly. But then you turn it up a little higher and then it feels warm, emitting more infrared and then it becomes visible, but deep red. Yeah, it's emitting visible light, but also still emitting all the more infrared than before. But it kind of stops there.

[Mordecai Mark McLow (Astrophysicist Guest)]

But it keeps. But you keep cranking it up.

[Neil deGrasse Tyson]

If you had a orange hot.

[Comedian/Co-host]

Wait, so you could have like a black hole in your kitchen.

[Neil deGrasse Tyson]

Well, we're getting there.

[Mordecai Mark McLow (Astrophysicist Guest)]

Not a good idea. X ray emission is unhealthy for human beings.

[Comedian/Co-host]

Oh, got it. Yep.

[Neil deGrasse Tyson]

So you keep turning it up. If you could, it would then glow white hot, then blue hot.

[Mordecai Mark McLow (Astrophysicist Guest)]

Like a welding torch.

[Neil deGrasse Tyson]

Right. But then that's all you can see. But it'll keep what's beyond violet, Ultra ultraviolet.

[Disney Vacation Club Announcer]

Ultraviolet.

[Comedian/Co-host]

Ultraviolet.

[Disney Vacation Club Announcer]

Cool.

[Mordecai Mark McLow (Astrophysicist Guest)]

How about that? And now you're getting your sunburns.

[Neil deGrasse Tyson]

Yeah. And so at a billion degrees, you

[Mordecai Mark McLow (Astrophysicist Guest)]

are way, you're way off into the X and gamma ray.

[Neil deGrasse Tyson]

X rays and gamma rays.

[Mordecai Mark McLow (Astrophysicist Guest)]

So you don't want to be too close to one of these.

[Neil deGrasse Tyson]

Okay. So hence the word active in active galactic nuclei.

[Mordecai Mark McLow (Astrophysicist Guest)]

So these objects are literally the brightest objects in the universe. And so we can see them across the universe out to, you know, 95% of the distance to the back. When you're looking across the universe, you're looking back in time. So 95% of the distance back to the Big Bang. We can see these things because they're so bright. Totally.

[Comedian/Co-host]

They're show offs of the milk galaxy.

[Mordecai Mark McLow (Astrophysicist Guest)]

Of the universe.

[Comedian/Co-host]

Of the universe.

[Mordecai Mark McLow (Astrophysicist Guest)]

The Milky Way does have a very massive supermassive black hole in its center. But it doesn't get a lot to eat. So it's kind of a wimpy, dim little thing.

[Neil deGrasse Tyson]

But back then, were we that, Were

[Mordecai Mark McLow (Astrophysicist Guest)]

we ever a quasar? There is actually evidence that quite recently, like just 5 million years or so ago, there was a much brighter outburst from our own galactic black hole. And there's now a shockwave, like running out of the galaxy.

[Neil deGrasse Tyson]

That's how you trace it, I guess. Yeah, yeah.

[Mordecai Mark McLow (Astrophysicist Guest)]

It was first discovered using the Fermi gamma ray satellite.

[Neil deGrasse Tyson]

Yeah. But is our black hole big? Do we have black hole envy here?

[Mordecai Mark McLow (Astrophysicist Guest)]

Oh, yes. We only have a million solar masses. The biggest quasars can be a billion solar masses. A thousand times bigger.

[Comedian/Co-host]

Yeah, it's embarrassing because, like, once you go big black hole, you really don'. Go back. And that's like something that every astrophysicist says.

[Mordecai Mark McLow (Astrophysicist Guest)]

That's right. Black holes do not give up mass easily. Putting them on a diet takes a very, very, very long time.

[Comedian/Co-host]

Wait, can you do. Can you tell me the size of these black holes in like, the continental United States analogy?

[Neil deGrasse Tyson]

Oh, yeah, sure, sure.

[Mordecai Mark McLow (Astrophysicist Guest)]

So a billion solar mass black hole,

[Neil deGrasse Tyson]

that's like the solar system, right?

[Mordecai Mark McLow (Astrophysicist Guest)]

Is a little smaller than the solar system. A stellar mass black hole, like one solar mass is, I want to say a kilometer or so.

[Neil deGrasse Tyson]

Yeah, I think that's right.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yeah. A mile. A mile, got it. It's not as big as Central Park.

[Comedian/Co-host]

Okay.

[Neil deGrasse Tyson]

Yeah. And if Earth were a black hole, which would never be, but if it were, it would be the size of a plum.

[Mordecai Mark McLow (Astrophysicist Guest)]

A marble.

[Comedian/Co-host]

Oh, gotcha.

[Neil deGrasse Tyson]

Somewhere around there. Yeah, yeah, yeah.

[Comedian/Co-host]

So compressed.

[Neil deGrasse Tyson]

But while this whole system is big, that's tiny compared to the whole galaxy. And gas clouds are way bigger than that.

[Mordecai Mark McLow (Astrophysicist Guest)]

Oh, so much bigger.

[Neil deGrasse Tyson]

When you talk about funneling them down to something as small as the size of our solar system, I mean, your

[Mordecai Mark McLow (Astrophysicist Guest)]

average gas cloud is, let's say, a million times as big as the distance from the Earth to the sun.

[Neil deGrasse Tyson]

Space is big.

[Comedian/Co-host]

Big, yeah. Space is like angeringly huge.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay, well, some people could think that they like their space.

[Neil deGrasse Tyson]

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[Commercial Narrator]

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[Comedian/Co-host]

Can you grab one more thing?

[Mordecai Mark McLow (Astrophysicist Guest)]

I'll come back up for you.

[Comedian/Co-host]

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[Capella University Announcer]

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[Comedian/Co-host]

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[Mordecai Mark McLow (Astrophysicist Guest)]

We're here to help protect the life you've built.

[Neil deGrasse Tyson]

Really?

[Mordecai Mark McLow (Astrophysicist Guest)]

I gotta have another one.

[Comedian/Co-host]

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[Capella University Announcer]

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[Neil deGrasse Tyson]

You have not stopped there, of course. You have explored the formation of planets in these environments.

[Mordecai Mark McLow (Astrophysicist Guest)]

So I started out by working on the formation of planets around normal, boring stars. And I went so far.

[Neil deGrasse Tyson]

Is that what we all care about?

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, I would think so, but you're bringing up weird planets. Okay, Right, Okay. So I started out just thinking about the thing we care about. How did the Earth form?

[Neil deGrasse Tyson]

Yeah.

[Mordecai Mark McLow (Astrophysicist Guest)]

And I went so far as to hire a postdoc, Vladimir Lyra, to study this with me. And we were going along perfectly happy studying planets moving around in the proto solar disk. And he made the mistake, or maybe the very wise decision to talk to some of our City University CUNY colleagues who were doing research here on AGNs.

[Neil deGrasse Tyson]

Oh, okay.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay. On the disk.

[Neil deGrasse Tyson]

Because we have here in our department, we have many frequent visitors from nearby universities with resonant interests.

[Mordecai Mark McLow (Astrophysicist Guest)]

In particular, we have an NSF funded partnership with cuny.

[Neil deGrasse Tyson]

What's the official nsf?

[Mordecai Mark McLow (Astrophysicist Guest)]

Official NSF official to bring students and faculty from campuses across the city to do research here at the research intensive American Museum of Natural History.

[Neil deGrasse Tyson]

Is that what pays for the pizza? Every Thursday there's like seven boxes of pizza come in. People only think when we're eating.

[Comedian/Co-host]

What's a favorite topping of the astrophysicist community. Is there like a way.

[Mordecai Mark McLow (Astrophysicist Guest)]

I believe we may ensure that all diets have an option.

[Comedian/Co-host]

Okay, yeah, okay.

[Mordecai Mark McLow (Astrophysicist Guest)]

But back to AGNs, which are kind of like pizzas because they have disks, very flat distributions of gas and dust around them. Because stuff falling onto an object, if that stuff can Cool off. Like gas can radiate and cool off. It will form not a ball around it, but a flat disk. Same thing happened in our solar system. It's a rotating disk, not like a pizza, but like a pizza being made.

[Comedian/Co-host]

Or like a sushi conveyor belt.

[Mordecai Mark McLow (Astrophysicist Guest)]

Let's stick with the pizza being made.

[Neil deGrasse Tyson]

I hate those. Because that means the sushi went in front of the.

[Disney Vacation Club Announcer]

A lot of people.

[Commercial Narrator]

Yeah.

[Mordecai Mark McLow (Astrophysicist Guest)]

Big Japanese scandal. So you've got this flat disk and there's stuff accumulating in the disk. It gets dirty and dusty and that dust starts to stick together. And. Well, if you're in a normal disk around a normal star like the sun, which isn't quite normal, it's bigger than average there. It makes planets like, say, this one that I can observe under my feet. However, if you're in a disk around a supermassive black hole 100 million times as massive as the sun, there's an awful lot of dust in that disk, and it's awful large. And you don't form three planets or eight planets. You form a million planets.

[Neil deGrasse Tyson]

So you made a million planet. Star system, black hole, planetary system, planetary

[Mordecai Mark McLow (Astrophysicist Guest)]

system, planetary system around the black hole. And this was a paper that we just had accepted a couple, like, two weeks ago.

[Comedian/Co-host]

Oh, my God. Breaking news.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yep.

[Disney Vacation Club Announcer]

Okay.

[Mordecai Mark McLow (Astrophysicist Guest)]

Although I will say so. Bhupendra Mishra was the lead author on that.

[Neil deGrasse Tyson]

How many authors are there?

[Mordecai Mark McLow (Astrophysicist Guest)]

Let's see. I think there are six.

[Neil deGrasse Tyson]

So this is typical when you have collaborations.

[Mordecai Mark McLow (Astrophysicist Guest)]

Absolutely.

[Neil deGrasse Tyson]

And some of them are CUNY.

[Mordecai Mark McLow (Astrophysicist Guest)]

Professor. Two of them are CUNY.

[Neil deGrasse Tyson]

CUNY. City University of New York.

[Mordecai Mark McLow (Astrophysicist Guest)]

Barry McKernan and Saavik Ford. Vladimir Lyra, who was a postdoc.

[Neil deGrasse Tyson]

Savic Ford is named for a character on Star Trek.

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, she named herself for it.

[Comedian/Co-host]

Oh, I was going to say. Wow, she really figured that out.

[Neil deGrasse Tyson]

No, no, she did. But I think it's official. I mean.

[Mordecai Mark McLow (Astrophysicist Guest)]

Oh, yeah, she publishes under that.

[Comedian/Co-host]

She admitted. Okay.

[Mordecai Mark McLow (Astrophysicist Guest)]

K E Savik for. Yes, yes.

[Neil deGrasse Tyson]

Okay.

[Mordecai Mark McLow (Astrophysicist Guest)]

Anyway, we showed that if you take standard planet formation theory, and this is the same trick that Vlad Berry and Savic did 15 years ago, to realize that black holes could move around like planets. If you take standard planet formation theory and apply it the dust, you find that it is very liable to go through all the stages that you would go through to make planets. Except they're really big planets because there's so much dust.

[Neil deGrasse Tyson]

So how big. How big are the solid mass?

[Comedian/Co-host]

What are we talking?

[Mordecai Mark McLow (Astrophysicist Guest)]

Jupiter mass? Solid rock planets. Except they're probably not rock. Cause they're probably degenerate in the centers.

[Neil deGrasse Tyson]

Wait, wait. So our Jupiter is big, but it's mostly gas?

[Mordecai Mark McLow (Astrophysicist Guest)]

It's mostly gas.

[Neil deGrasse Tyson]

You're saying you can make a Jupiter sized planet that's rocky, it silicates.

[Mordecai Mark McLow (Astrophysicist Guest)]

Ooh.

[Neil deGrasse Tyson]

Ouch.

[Commercial Narrator]

Ooh.

[Mordecai Mark McLow (Astrophysicist Guest)]

So, yeah.

[Comedian/Co-host]

Does that mean also that its gravity is like extra annoying?

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes.

[Comedian/Co-host]

Got it. Because it's extra annoying being like strong.

[Neil deGrasse Tyson]

Yeah, I understood that. Yeah, we totally understood you again.

[Mordecai Mark McLow (Astrophysicist Guest)]

Totally.

[Comedian/Co-host]

Sometimes I just need to like translate for the fact.

[Mordecai Mark McLow (Astrophysicist Guest)]

You're absolutely right. Because the gravity at the cloud tops of Jupiter, we won't call it the surface, but at the cloud tops of Jupiter is quite reasonable. It's not far off from.

[Neil deGrasse Tyson]

Is it like 10 times gravity?

[Mordecai Mark McLow (Astrophysicist Guest)]

No, no, no, no.

[Neil deGrasse Tyson]

Not even.

[Mordecai Mark McLow (Astrophysicist Guest)]

Not even. It's close to Earth's gravity because Jupiter's so big and low density. But the gravity at the surface of one of these monsters would perhaps be ten times Earth's gravity. I don't know, I haven't done the calculation.

[Neil deGrasse Tyson]

It's an easy calculation, but you're the

[Mordecai Mark McLow (Astrophysicist Guest)]

same density and, you know, 10 times the radius.

[Neil deGrasse Tyson]

We don't expect to find life on any of these because there's no home star to give nourishing energy to.

[Mordecai Mark McLow (Astrophysicist Guest)]

No, it's rather worse. There's a home center of the accretion disk glowing in X rays and gamma rays. It will provide plenty of energy, but it might not be in a form conducive to life as we know it's still to biology. That would be my suggestion.

[Comedian/Co-host]

Is there a biology that we don't know of that could maybe handle it

[Mordecai Mark McLow (Astrophysicist Guest)]

is an excellent question that we don't

[Neil deGrasse Tyson]

know the answer to me is the Hulk biology.

[Mordecai Mark McLow (Astrophysicist Guest)]

Gamma ray biology.

[Comedian/Co-host]

The Hulk into your simulator and see

[Mordecai Mark McLow (Astrophysicist Guest)]

how does he do? We're going to have to get his specifications.

[Comedian/Co-host]

Yeah, yeah, I want to see this.

[Neil deGrasse Tyson]

So if all you need is dust, which are the larger molecules, larger gathering

[Mordecai Mark McLow (Astrophysicist Guest)]

of atoms, minerals, okay, these are silicates, these are dust, like, kind of like we find on the Earth, except it formed in space. Even though spaces, as noted, very large. The rocky atoms of silicon and oxygen and magnesium tend to find each other. And once they find each other, they stick together. And so they form little tiny dust grains like a nanometer in size in deep space. But when you collect all of them together, whether it be in a protostellar disk or a supermassive black hole disk, they can find each other and stick together. And actually that's something else I've been working on recently is showing that they might be a Lot stickier than people have thought.

[Neil deGrasse Tyson]

So when they stick together, they stay,

[Mordecai Mark McLow (Astrophysicist Guest)]

they appear to stay well until they get big enough and then they break apart when they slam into each other. And that's actually a, that's a whole process. That's a big question in planet formation theory is how do you get them to stop beating each other up and fragmenting.

[Comedian/Co-host]

Yeah. Cause is it also, I mean, partially. What you're describing almost sounds like a sandcastle. Like they're sort of sticking together like a sandcastle.

[Mordecai Mark McLow (Astrophysicist Guest)]

That is an excellent description of an asteroid. We call them rubble piles, but it's really a sandcastle.

[Comedian/Co-host]

But it's so that it's so they're pretty vulnerable.

[Mordecai Mark McLow (Astrophysicist Guest)]

They're fragile. Yeah, they're totally fragile. How did we learn this back, oh, 30 years ago, a comet swung too close to Jupiter. Comet Shoemaker Levy 9. You're supposed to not just make faces.

[Neil deGrasse Tyson]

Comet Shoemaker Levy. This is a first ever observation of a comet slamming into one of our own planets. Yes, yes.

[Comedian/Co-host]

Or do you memorize all of the comets?

[Neil deGrasse Tyson]

No, just the book.

[Comedian/Co-host]

Because I was very impressed if you had them all down.

[Mordecai Mark McLow (Astrophysicist Guest)]

Oh, no, no, no, they're.

[Comedian/Co-host]

I'll remove being impressed. I am no longer impressed. Go ahead.

[Mordecai Mark McLow (Astrophysicist Guest)]

Very good. Back to. As you were.

[Neil deGrasse Tyson]

And I have to just put in here that duo, by the way, the Shoemaker Levy 9. Okay.

[Mordecai Mark McLow (Astrophysicist Guest)]

It's really Shoemaker, Shoemaker, Levy, others that

[Neil deGrasse Tyson]

they're, they're active bunch.

[Mordecai Mark McLow (Astrophysicist Guest)]

Oh yeah.

[Neil deGrasse Tyson]

And that collaboration had a leftover asteroid that they named in my honor.

[Comedian/Co-host]

Yes.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay. I knew you had an asteroid, but I didn't know it was the Shoemaker leaving.

[Neil deGrasse Tyson]

It was the Shoemaker leaving and the plaque is right up there.

[Comedian/Co-host]

Sorry, quick question. Who decides these things? Is it you?

[Neil deGrasse Tyson]

The discoverer. But it has to be approved.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay, you can't be rude.

[Neil deGrasse Tyson]

So it was that duo. That's how.

[Mordecai Mark McLow (Astrophysicist Guest)]

Trio.

[Neil deGrasse Tyson]

Trio. That's how fertile a discovery group that Gene Shoemaker, Carolyn Shoemaker and David Levy. And David Levy, yeah. They've discovered comets and asteroids and all kind of things.

[Mordecai Mark McLow (Astrophysicist Guest)]

And Gene Shoemaker also pretty much was the originator of the theory of craters. Like what happens when something, a big rock slams into a planet? It makes a crater. He described how. And so that's.

[Neil deGrasse Tyson]

It sounds obvious, I know.

[Comedian/Co-host]

I was just gonna say, like I can also ask my 7 year old daughter about the theory of craters.

[Mordecai Mark McLow (Astrophysicist Guest)]

I think she'd come up with the same thing. That's how fundamental his work was. Because before Gene Shoemaker, people looked at the moon and saw volcano craters.

[Comedian/Co-host]

Right.

[Mordecai Mark McLow (Astrophysicist Guest)]

Not the.

[Comedian/Co-host]

Okay.

[Neil deGrasse Tyson]

Every crater was a volcanic caldera.

[Comedian/Co-host]

Yeah.

[Mordecai Mark McLow (Astrophysicist Guest)]

Like Crater Lake.

[Neil deGrasse Tyson]

They're not completely crazy to think so.

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, Crater Lake is a volcanic caldera.

[Neil deGrasse Tyson]

Right. They're not crazy to think so.

[Mordecai Mark McLow (Astrophysicist Guest)]

They were just wrong.

[Neil deGrasse Tyson]

It's possible to be. That makes complete sense. You're just wrong. Okay. That happens in science all the time. It's very frustrating. But the reason is the argument against them being asteroids was every crater is a perfect circle on the Moon. And no one is thinking asteroids are coming straight in. Surely some are coming at an angle. If you come in on an angle, you'd expect an oval.

[Comedian/Co-host]

Right.

[Neil deGrasse Tyson]

Most of them should be ovals, but everyone was a perfect circle. And so that's the tension between the two arguments in the two camps. And it wasn't until we had, like we can model.

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, until Gene Shoemaker came along and said, no, they should be circles.

[Neil deGrasse Tyson]

No, no. Someone had to demonstrate with a computer simulation that a high speed impact, when it hits, it explodes.

[Mordecai Mark McLow (Astrophysicist Guest)]

It vaporizes.

[Neil deGrasse Tyson]

Yeah. And that explosion makes a perfect circle even if it comes in at an angle.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay, but we're off the topic.

[Neil deGrasse Tyson]

Yes.

[Mordecai Mark McLow (Astrophysicist Guest)]

Which is that when Comet Shoemaker Levy 9 passed close to Jupiter, it felt gravitational forces from Jupiter, but it was coming by at a fair distance. And those gravitational forces were not strong. Massive planet gravitational forces, they were forces equivalent to 18 of an inch of water in Earth's gravity. How much pressure does that put on your plate? Not much. Nothing. That's all the force that tore that comet apart into 21 pieces. That's how weakly bound it was. And that's why I say it was. Your sandcastle is exactly right.

[Comedian/Co-host]

Oh, I feel so smart right now. Yes. I love this moment.

[Mordecai Mark McLow (Astrophysicist Guest)]

You're welcome.

[Neil deGrasse Tyson]

Yeah. And so just to show there's still a huge frontier for us to understand these objects and you got people, good people working on it, taking us, including

[Comedian/Co-host]

the guy that said when a thing hits another thing, it forms a crater.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes, yes.

[Comedian/Co-host]

Which, like, I can't believe somebody. Yeah, somebody had to do it for. Bless that guy.

[Neil deGrasse Tyson]

Yeah. Yeah. So we got questions from our audience who've been specifically clued to your research profile. And the questions will emanate from that. So what do you have here for us, Nege? I haven't seen the question. You haven't seen them either?

[Mordecai Mark McLow (Astrophysicist Guest)]

I have not seen them.

[Comedian/Co-host]

I've seen them. I think they're great. Here we go. Tatiana here from Ottawa, Ontario. I'm 15 years old and finally asking my first StarTalk question.

[Mordecai Mark McLow (Astrophysicist Guest)]

Congratulations.

[Comedian/Co-host]

My question is, what are and how do supersonic turbulent flows and magnetic fields regulate star formation inside molecular clouds?

[Mordecai Mark McLow (Astrophysicist Guest)]

How many hours do I get?

[Disney Vacation Club Announcer]

I mean.

[Comedian/Co-host]

And then she's not done. Do they work together to stabilize the process, or does their interaction create chaos?

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes, yes and yes.

[Neil deGrasse Tyson]

Yeah, naively, it feels like that would just mess up the whole thing. You're getting coherent planets out of this, aren't you?

[Mordecai Mark McLow (Astrophysicist Guest)]

Stars, stars, stars. Okay, okay, yes. The turbulence stirs things up and it also squeezes some of the gas. And so the squeezed gas, gravity can take hold and start the collapse process. But the stirring prevents more gas from getting grabbed by gravity and collapse down to form stars. So it's both. Both. And the stirring actually wins. So the more turbulence you have, the less star formation you have.

[Neil deGrasse Tyson]

Okay, but when you have a little pocket that's slightly more dense, that attracts more material, that makes it even more dense. And so it's a runaway.

[Mordecai Mark McLow (Astrophysicist Guest)]

It's a runaway. Once you get started.

[Neil deGrasse Tyson]

Once you get out of the starting gates.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes. Okay, now then what happens is that as you start forming stars, the biggest, most massive of them pump huge amounts of energy back into the gas, whether it be through jets or ionizing radiation or stellar winds or ultimately supernova explosions, and that chases the gas away, and then you don't get any more star formation.

[Neil deGrasse Tyson]

Okay, now how do you know all this?

[Mordecai Mark McLow (Astrophysicist Guest)]

Because I've done simulations of it, and then I compared those simulations to what observers saw because you have nothing to compare to so bad.

[Neil deGrasse Tyson]

So if you didn't have observations to compare it to, you're just kind of presuming your results are real.

[Mordecai Mark McLow (Astrophysicist Guest)]

I'm playing in the sandbox without any constraints, and then I can make sandbox analogy here, I'm running with it here.

[Comedian/Co-host]

But you like. So how much? Like what level of confidence, percentage wise, is it.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay, so the point about constraints is important because otherwise someone else can come along and say, no, no, no, no, no, no, the magnetic fields. And you're going to have to wait for the neutral atoms to drift through the ions to ever, ever make a star. Without observations, we can't tell who's right because he can say, of course, it works like this. I've written 20 papers on it. And I can say, but my programs don't show that.

[Comedian/Co-host]

But.

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, you know, so I wrote my programs wrong.

[Neil deGrasse Tyson]

One possible. You just went too quickly past that. I'm sorry, what you just said was that your naysayer could be right and maybe your software could be right. Bugs in it, or is there some approximations?

[Mordecai Mark McLow (Astrophysicist Guest)]

Approximations. We always Every model has approximations.

[Neil deGrasse Tyson]

We don't know until.

[Mordecai Mark McLow (Astrophysicist Guest)]

Until you compare to the observations.

[Neil deGrasse Tyson]

There you go. Okay.

[Comedian/Co-host]

And then you get a reasonable level

[Mordecai Mark McLow (Astrophysicist Guest)]

of confidence, Then you build up your confidence. And of course, then you argue about what the observations mean and whether there was noise in the telescop. You know, what assumptions went into the interpretation of the observations. But ultimately, this is how science progresses. You come up with an idea, and then you have to. Then other people come up with different ideas, you argue about it, and you settle it by reference to the real world.

[Comedian/Co-host]

Oh, not a duel. Okay, sorry.

[Mordecai Mark McLow (Astrophysicist Guest)]

We try to avoid that, and most of the time we succeed.

[Neil deGrasse Tyson]

Somebody shot him in his buttocks. No, but it's evidence that arriving at what is objectively true in the actual universe is messy.

[Mordecai Mark McLow (Astrophysicist Guest)]

Totally. So messy.

[Neil deGrasse Tyson]

So messy. And the strength with which you argue your point ultimately is not the arbiter.

[Mordecai Mark McLow (Astrophysicist Guest)]

No, unfortunately, it might be easier that way.

[Neil deGrasse Tyson]

And it doesn't matter how articulate you are or how charismatic you are. We have the ultimate.

[Mordecai Mark McLow (Astrophysicist Guest)]

You still have to win.

[Neil deGrasse Tyson]

Judge, jury, and executioner is nature.

[Mordecai Mark McLow (Astrophysicist Guest)]

That is the agreement the people doing science have made with each other.

[Neil deGrasse Tyson]

It's an implicit agreement.

[Mordecai Mark McLow (Astrophysicist Guest)]

One hopes it's explicit. But is that we will settle our arguments ultimately by reference to reproducible experiments and observations.

[Neil deGrasse Tyson]

Yes. So either I'm right and you're wrong, you're right and I'm wrong, or we're both wrong. It'll be decided by more data or better data.

[Mordecai Mark McLow (Astrophysicist Guest)]

That's right.

[Neil deGrasse Tyson]

Yeah. Okay.

[Mordecai Mark McLow (Astrophysicist Guest)]

And that is the central tenet of science.

[Neil deGrasse Tyson]

Where does the magnetic field come from?

[Mordecai Mark McLow (Astrophysicist Guest)]

The magnetic field comes from a dynamo. So dynamos happen when you get some sort of stirring of charged gas or charged things. So like a dynamo in a power station, the charge is running through wires.

[Neil deGrasse Tyson]

And it's spinning.

[Mordecai Mark McLow (Astrophysicist Guest)]

And it's spinning.

[Neil deGrasse Tyson]

Yes, yes.

[Mordecai Mark McLow (Astrophysicist Guest)]

And in the universe, or in the Earth, the dynamo is turbulent, swirling magma deep down in the Earth that is kept molten by the pressure and radioactivity of the Earth. And it swirls around and makes the Earth's magnetic field. And that's a dynamo. Well, same in the sun, except there it's plasma. In galaxies, the charged gas between the stars forms a dynamo stirred by supernova explosions and by gravity.

[Neil deGrasse Tyson]

So if you didn't have the turbulence,

[Mordecai Mark McLow (Astrophysicist Guest)]

you wouldn't get the dynamo.

[Neil deGrasse Tyson]

You wouldn't have a magnetic field.

[Mordecai Mark McLow (Astrophysicist Guest)]

You would not have magnetic field.

[Neil deGrasse Tyson]

So they go hand in hand.

[Mordecai Mark McLow (Astrophysicist Guest)]

One generates the other.

[Neil deGrasse Tyson]

Okay.

[Comedian/Co-host]

It's like they're in heat and then they give birth to this.

[Mordecai Mark McLow (Astrophysicist Guest)]

Sure. Maybe I Think you're stretching the field here, but if you stretch the field and twist it and rotate, you will get a dynamo.

[Comedian/Co-host]

Great, thank you.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay, so the first dynamos happen when the very, very first stars form. And ever since then, we've had significant magnetic fields running around, getting stretched and twisted and folded to make more magnetic fields.

[Neil deGrasse Tyson]

There we are.

[Comedian/Co-host]

There we are. Should we move on to the next question?

[Neil deGrasse Tyson]

Thank you for that.

[Comedian/Co-host]

All right, Ismael Valdez here asking my first question from Del Mar, Chile. Okay. In regards to stars and gas giants, if Jupiter were sufficiently massive, would the pressure ignite? Would its pressure ignite its lighter components?

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes.

[Comedian/Co-host]

Furthermore, do the sun, or stars in general share elements with gas giants, like a rocky core, or is it fused gas all the way through? Which sounds like a tough meal at Taco Bell? I don't know.

[Disney Vacation Club Announcer]

Go ahead.

[Neil deGrasse Tyson]

Let me modify that just a little bit. If we had the capacity to dump mass onto Jupiter, could we ignite it one day?

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes. He had two questions. First question is, if you increase Jupiter's mass, does it ignite? And the answer is yes, if you increase Jupiter's mass enough, like. Well, if you get it up to about, I want to say, ten times the mass of Jupiter, you get the deuterium burning, the heavy hydrogen with extra neutrons, and that lasts for a little while, but there's not a whole lot of deuterium in the universe. It's like, I don't know, a part in a hundred thousand, a few parts in 100,000. So that's. You get a little flash of light, you know, for a couple of maybe a million, a couple hundred thousand years, and then it's gone. And that's a brown dwarf, and they exist. And we've got one of the world's premier research groups on the topic right upstairs here, run by Jackie Faraday, because

[Neil deGrasse Tyson]

we just went down the hall to get Mordecai. Right?

[Mordecai Mark McLow (Astrophysicist Guest)]

Yeah, yeah, yeah. I traveled a long way. I want my per diem in the

[Neil deGrasse Tyson]

Department of Astrophysics of the American Museum of Natural History.

[Mordecai Mark McLow (Astrophysicist Guest)]

That's a brown dwarf. Now, if you keep piling mass on and get up to in Jupiter masses, like 80 times.

[Neil deGrasse Tyson]

Oh, that meant that much.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yeah, 80 times the mass of Jupiter, which is a little under a tenth.

[Neil deGrasse Tyson]

You could just drop Saturn onto it. No, that would be amazing to watch,

[Mordecai Mark McLow (Astrophysicist Guest)]

but not nearly enough.

[Neil deGrasse Tyson]

That still wouldn't ignite it.

[Mordecai Mark McLow (Astrophysicist Guest)]

No, no, not even close.

[Neil deGrasse Tyson]

Not even close.

[Mordecai Mark McLow (Astrophysicist Guest)]

Not even close.

[Comedian/Co-host]

Well, so you, as you said earlier, like, something like that is just like a couple hundred thousand years. It's like dumb.

[Mordecai Mark McLow (Astrophysicist Guest)]

That's the brown dwarf. Don't call brown dwarfs dumb around here. Okay.

[Comedian/Co-host]

No, I'm just trying to understand. Cause you made that sound like not nothing. Like it's not nothing.

[Mordecai Mark McLow (Astrophysicist Guest)]

It's fusion, but it's not a lot of fusion.

[Comedian/Co-host]

Okay.

[Neil deGrasse Tyson]

Even what he's about to say. Wait, wait, wait. That's a.

[Mordecai Mark McLow (Astrophysicist Guest)]

It's a flash in the pan.

[Comedian/Co-host]

Gotcha.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay, but if you get up to 80 times, then you can ignite hydrogen and there's a lot more hydrogen. That's what Jupiter's mostly made of. Then you've got a very low mass star and very low mass star sit there and simmer for longer than the current lifetime of the universe. So that will keep going and going and going.

[Comedian/Co-host]

So that's way more than 200,000.

[Mordecai Mark McLow (Astrophysicist Guest)]

It's way more than the life of the universe. It's like 10 times the life of the universe. No. A hundred times the current life of the universe.

[Neil deGrasse Tyson]

Yeah. But question right now, Jupiter has a rocky core.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes.

[Neil deGrasse Tyson]

What happens to that rocky core? Because it's kind of related to this question.

[Mordecai Mark McLow (Astrophysicist Guest)]

Absolutely, yes. Let's go, let's go, let's go.

[Neil deGrasse Tyson]

Bring it on.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay, so what happens is it gets completely overwhelmed, bound by all the hydrogen, and just gets mixed in because the hydrogen is sitting there fusing. So you have a little tiny rocky core.

[Neil deGrasse Tyson]

Now the sun, why doesn't it just vaporize the rocky core?

[Mordecai Mark McLow (Astrophysicist Guest)]

Yeah, that's what I'm saying. Okay. It's not rocky anymore. What it is, the elements of the former, of the rock core formerly known as rocky, are now part of the fusing vaporized hydrogen in the center of the object. Because it's now, you know, far hotter than anything any rock has any right to withstand. So it's vape. It's rock.

[Neil deGrasse Tyson]

It's vaporized by the rock.

[Mordecai Mark McLow (Astrophysicist Guest)]

Gotcha. That's right. Now remember, the sun also has silicon and magnesium and aluminum and oxygen in it. It's just all mixed in with the hydrogen.

[Neil deGrasse Tyson]

Right. So yeah, the sun, you might think, would have a rocky core the way Jupiter did, but for that same reason. It's all.

[Mordecai Mark McLow (Astrophysicist Guest)]

It's too hot.

[Neil deGrasse Tyson]

It can't be anything other than loose atom.

[Mordecai Mark McLow (Astrophysicist Guest)]

Loose ions and electrons even, can even be atoms. Except on the very, very surface, an

[Neil deGrasse Tyson]

atom is a nucleus plus electrons.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes.

[Neil deGrasse Tyson]

All the electrons are gone.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes. In the center, they're all gone. They're just roaming freely away from their parent atoms.

[Comedian/Co-host]

Got it.

[Mordecai Mark McLow (Astrophysicist Guest)]

Here's your cue.

[Comedian/Co-host]

Yeah. Like they're having a rebellious phase.

[Mordecai Mark McLow (Astrophysicist Guest)]

Oh, they are. Long gone. Never to return.

[Comedian/Co-host]

Never to return. They're not just like TPing their geometry teacher's house or something?

[Mordecai Mark McLow (Astrophysicist Guest)]

No, no. They have won TPing.

[Neil deGrasse Tyson]

That's a thread. Toilet papering. Yes. Have you done that?

[Comedian/Co-host]

I have. I TP'd once in my day.

[Neil deGrasse Tyson]

This is stories. Tell your offspring.

[Mordecai Mark McLow (Astrophysicist Guest)]

I'm afraid we didn't do that. In the center of New York City because a six story apartment building is hard to see.

[Comedian/Co-host]

You're just doing toilet paper on someone's door and it's a lot less satisfying.

[Capella University Announcer]

Yeah.

[Comedian/Co-host]

Can't imagine.

[Disney Vacation Club Announcer]

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[Comedian/Co-host]

It's like a dream.

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Discover more [e-mail] this is a timeshare solicitation and other offer. Registration requirements haven't been met. Some benefits require additional eligibility. Theme park admissions.

[Capella University Announcer]

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[Mordecai Mark McLow (Astrophysicist Guest)]

I'm Nicholas Costella and I'm a Proud supporter of StarTalk on Patreon. This is StarTalk with Neil DeGrasse Tys.

[Neil deGrasse Tyson]

Time for a few more questions. What do you have? Okay.

[Comedian/Co-host]

Okay. Let's see. Hello. How is dark matter incorporated into your simulations? Random distribution or what?

[Neil deGrasse Tyson]

Okay, who told you?

[Comedian/Co-host]

Oh, sorry. And this question is from Ben Grund.

[Mordecai Mark McLow (Astrophysicist Guest)]

Great question. And the answer is any which way I can. So sometimes we actually put in particles in the simulation and watch them roam around under the force of gravity. And, well, they're very massive, massive particles, but they still behave like dark matter because they don't interact with the gas except by gravity.

[Neil deGrasse Tyson]

Other times you just said, since we don't actually know what dark matter is.

[Mordecai Mark McLow (Astrophysicist Guest)]

Oh, no, no, no. We're not even going there.

[Neil deGrasse Tyson]

No, no. But you know it has gravity.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes.

[Neil deGrasse Tyson]

Your simulation has to get it somehow. So you sprinkle in. You invent a particle that interacts only by gravity and has enough mass, enough gravity to match the observed dark matter. Okay, yes. So this is by, as they say, by fiat. You do this.

[Mordecai Mark McLow (Astrophysicist Guest)]

Is that the way I use the word?

[Disney Vacation Club Announcer]

Right.

[Mordecai Mark McLow (Astrophysicist Guest)]

I mean, you could say, if I

[Comedian/Co-host]

understood what any of these things were, I could weigh in on. If you used fiat correctly.

[Mordecai Mark McLow (Astrophysicist Guest)]

I wouldn't say it's by fiat in the sense that the whole simulation, by that definition, is by fiat. Right. I've added in a field of gas, I've added in star particles. So it's just one element of the

[Neil deGrasse Tyson]

simulation way to get a source of gravity without having to worry about it.

[Mordecai Mark McLow (Astrophysicist Guest)]

After that, it behaves like dark matter. The simpler way to do this, which I also sometimes do if I can get away with it, is to simply put in a gravitational field that reproduces the dark matter distribution and then let that handle it without having to actually do track particles. Without having to track particles and pay attention and do accounting and get bugs and all the rest.

[Neil deGrasse Tyson]

All right, so is it smoothly. It's a smooth field.

[Mordecai Mark McLow (Astrophysicist Guest)]

It's smooth if you're on a subgalactic scale. But if you're on a, you know, a galaxy forming scale, it's very, very clumpy because the clumps are the galaxies. So in that sense, when I'm simulating the formation of the first galaxies, then we're seeing big clumps of dark matter that the gas falls into, and then you've a galaxy.

[Neil deGrasse Tyson]

So I've heard this. I think it's right that dark matter, whatever it is, is so prevalent that when you just. When we look at and describe stars and galaxies, this is the froth on an Ocean.

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, 1/6th of the mass of the galaxy is in anything visible. Stars, planets, gas, comets, all of that, 1/6 of the mass, 85% of the gravity is from dark matter.

[Neil deGrasse Tyson]

It's something. You don't even know what it is.

[Mordecai Mark McLow (Astrophysicist Guest)]

We know it exerts gravity and we know it doesn't move at light speed. That's why it's cold dark matter.

[Comedian/Co-host]

But is there like, an area like that doesn't have any. Like, how Wyoming doesn't have people? Like, is there an area of the galaxy where, like, there's no dark matter?

[Mordecai Mark McLow (Astrophysicist Guest)]

Wyoming doesn't have people. Voids don't have dark matter, while clusters have lots of dark matter and filaments have, well, intermediate amounts of dark matter. They're like Interstates.

[Comedian/Co-host]

Okay.

[Mordecai Mark McLow (Astrophysicist Guest)]

So, yeah, people cluster around the.

[Comedian/Co-host]

So evenly distributed.

[Mordecai Mark McLow (Astrophysicist Guest)]

Absolutely not evenly distributed. Not in the universe. That's why we call it the cosmic web. Because it looks like spider webs, like with thin filaments and then big spaces in between.

[Comedian/Co-host]

Right.

[Neil deGrasse Tyson]

So web is. We say web now, but I remember when a cross section of a sponge. Does a sponge still work as a sponge? Still works and sort of areas around it and places where you intersect.

[Mordecai Mark McLow (Astrophysicist Guest)]

These days we usually talk about webs.

[Neil deGrasse Tyson]

Okay, that's fine.

[Comedian/Co-host]

Ditch the sponge.

[Neil deGrasse Tyson]

I was kind of into sponges, though.

[Comedian/Co-host]

I mean, I lie. I know you only got.

[Mordecai Mark McLow (Astrophysicist Guest)]

Interesting analogy for the interstellar medium, too.

[Neil deGrasse Tyson]

Yeah.

[Mordecai Mark McLow (Astrophysicist Guest)]

You know, Chris McKee and Don Cox arguing about is it a sponge or is it little round clouds?

[Neil deGrasse Tyson]

I had a cameo in spongebob. I was Neil de Bass. Tyson Astro fishes. Spongebob. I'm sticking to sponge.

[Mordecai Mark McLow (Astrophysicist Guest)]

You got it.

[Neil deGrasse Tyson]

Okay, thank you.

[Mordecai Mark McLow (Astrophysicist Guest)]

You can have. Thank you for granting the cosmological sponge.

[Neil deGrasse Tyson]

Yes, thank you. Thank you. Time for a couple more.

[Comedian/Co-host]

Okay, let's see.

[Mordecai Mark McLow (Astrophysicist Guest)]

We're on a roll here.

[Neil deGrasse Tyson]

Yes, we are.

[Comedian/Co-host]

So, Gavin Bamber from North Vancouver, please visit. They add. How long does it take to form a star or planet? Is it the same process? We're both in the same star stuff.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay. I believe the answer is yes and yes. And so how long does it take to form a star? The main formation phase, when most of the stuff comes down is maybe a hundred thousand years, but it trickles along. Yeah, that's like the main accretion phase, but it's going to trickle along with a disk and accreting more mass and forming planets for a couple of million years.

[Neil deGrasse Tyson]

So you'll form a star before you form the planets?

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, that's an ongoing controversy. That was the idea. That used to be the idea.

[Neil deGrasse Tyson]

Like, wouldn't that be the case? Right. You'd think.

[Mordecai Mark McLow (Astrophysicist Guest)]

You would think. But nowadays, the more we examine the question, the faster the planets seem to form. And so now I would actually say that the first planets form during that main accretion phase. Very, very f. But then you continue to form planets and planetary like things for several million years.

[Neil deGrasse Tyson]

And once again, you're forming crystal meteorites in a disk.

[Mordecai Mark McLow (Astrophysicist Guest)]

Once again in a disk. It's all dust and gas and gas.

[Neil deGrasse Tyson]

I have an accretion disk right here.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yeah, yeah. If you want to get brighter, eat

[Comedian/Co-host]

more like a quasar that takes so long. It just like everyone has to be really committed to that planet for it to form. You know what I mean?

[Mordecai Mark McLow (Astrophysicist Guest)]

Because it takes a Few million years.

[Comedian/Co-host]

Oh my gosh.

[Mordecai Mark McLow (Astrophysicist Guest)]

On the other hand, where are you going to go? You're stuck world in the this disc.

[Comedian/Co-host]

Go. Might as well keep doing it. Yeah, let's get it going. Eventually we'll have an Arby's here or whatever.

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, now the development of Arby's takes a lot longer. That's billions of years. Observably.

[Neil deGrasse Tyson]

As Carl Sagan said, how do you make an apple pie? You start with a big bang.

[Comedian/Co-host]

Right.

[Mordecai Mark McLow (Astrophysicist Guest)]

Go find the chicken.

[Comedian/Co-host]

Okay, time for another question.

[Neil deGrasse Tyson]

Yeah, let's do it.

[Comedian/Co-host]

After all the model runs, how often do planets form with a satellite as large by percentage of mass of the planet as our moon?

[Neil deGrasse Tyson]

Good one.

[Mordecai Mark McLow (Astrophysicist Guest)]

That's a very good one. And the answer is that the computer simulations aren't high enough resolution to really get a good answer to that yet. And so that is a current research question. Otherwise, meaning.

[Neil deGrasse Tyson]

But we have all these planets with wimpy moons.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes.

[Neil deGrasse Tyson]

Right.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes.

[Neil deGrasse Tyson]

So we already know.

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, observationally, we know in one planetary system with one set of initial conditions that moons like the Earth are pretty rare. And that's all we know. How many planetary systems do we know of?

[Neil deGrasse Tyson]

Well, it's growing now.

[Mordecai Mark McLow (Astrophysicist Guest)]

6,000 and counting. It's growing, it's growing fast and it's going to keep growing. And we don't know if any of those planets have more moons because observationally, we haven't been able to see them because it's really hard to see a moon around a planet. It's already really, really hard to see a planet, much less a moon. And David Kipping up at Columbia thinks he's found a moon, but everybody else is staying on the fence and saying maybe it's a moon.

[Neil deGrasse Tyson]

David Kipping, we've had him on Star Trek.

[Mordecai Mark McLow (Astrophysicist Guest)]

I'm sure you have.

[Capella University Announcer]

Yeah.

[Neil deGrasse Tyson]

He's got a lab called the Cool World Lab.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes.

[Neil deGrasse Tyson]

Which is pretty cool.

[Mordecai Mark McLow (Astrophysicist Guest)]

Pretty cool. And he's got a podcast.

[Neil deGrasse Tyson]

Yes.

[Mordecai Mark McLow (Astrophysicist Guest)]

Which funds that lab, Cool World's best.

[Comedian/Co-host]

Your simulations sometimes see like a hint of a moon.

[Mordecai Mark McLow (Astrophysicist Guest)]

My. Well, I don't do those simulations, but our simulations, the fields, you can make moons. And we know, I mean, we certainly know how to make the Earth's moon slam a Mars sized planet into a proto Earth. And that works shockingly well, as evidenced by the Apollo astronauts bringing back rocks that had the same composition as the Earth because they formed, because they never

[Neil deGrasse Tyson]

went to the moon to begin with.

[Mordecai Mark McLow (Astrophysicist Guest)]

They worked from the Earth to the moon.

[Neil deGrasse Tyson]

Cut that out in the edit.

[Mordecai Mark McLow (Astrophysicist Guest)]

Thank you.

[Neil deGrasse Tyson]

But that meant that the moon didn't form organically with the Earth it formed afterwards. Afterwards.

[Mordecai Mark McLow (Astrophysicist Guest)]

But now what the Earth is made of, of course, is also a mixture of proto Earth and I think they call it Aries, the Mars size that I'm.

[Neil deGrasse Tyson]

No, no, it's Theia. Theia. Theia.

[Mordecai Mark McLow (Astrophysicist Guest)]

Isn't Theia the proto Earth and Ares the proto moon? Oh, I mean the proto.

[Neil deGrasse Tyson]

I think Theia is the proto slammer.

[Mordecai Mark McLow (Astrophysicist Guest)]

Confirming now via NASA that the ancient proto planet that we collided with was Theia.

[Neil deGrasse Tyson]

Okay, so shockingly successful is this model that we even named the object that doesn't exist anymore.

[Comedian/Co-host]

That's right, the impact object.

[Neil deGrasse Tyson]

Object which is obliterated and became part of the. We gave it a name.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes.

[Neil deGrasse Tyson]

That's cool.

[Mordecai Mark McLow (Astrophysicist Guest)]

However, we can do those sorts of calculations for planets elsewhere, but to get the frequencies, that means a lot of calculation. We don't have enough computers to do that currently.

[Neil deGrasse Tyson]

Well, I love me my moon because our moon is the same size on the sky as the sun. So we have beautiful eclipses.

[Comedian/Co-host]

Oh, I love it.

[Neil deGrasse Tyson]

Nobody else has eclipses like that at Jupiter. It's got moons, but the sun is far. The moons are small. Nothing matches up the way our moon and our. So what is it? The moon is 400 times closer and 1 400th the size.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yep.

[Neil deGrasse Tyson]

So everything ratios exactly.

[Comedian/Co-host]

Exactly to the yang.

[Neil deGrasse Tyson]

Yeah.

[Mordecai Mark McLow (Astrophysicist Guest)]

And that's how you get eclipse chasers.

[Neil deGrasse Tyson]

Yeah. It's the greatest spectacle of nature.

[Comedian/Co-host]

A total solar second only to Manhattanhenge, which is also something because I love a Manhattanhenge. Oh my gosh, yes, thank you. That's because of you. Yeah, I followed your dates.

[Neil deGrasse Tyson]

Oh, okay. So Mordecai, time for one more question.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay.

[Neil deGrasse Tyson]

We've been going.

[Mordecai Mark McLow (Astrophysicist Guest)]

It better be a good one.

[Neil deGrasse Tyson]

And you're a good question answerer. You've been succinct and efficient.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay, I will ramble.

[Comedian/Co-host]

No, no, don't lay the question on us. Here we go from Emile Rougeau, who describes himself as a man who has forgotten what curiosity is. As once said before by you, Dr. McLo, eight to 10 years ago, quote, we live in a time where we have understood that the universe is far stranger than we would have thought. Have these thoughts changed over the years or have they made more problems for you?

[Mordecai Mark McLow (Astrophysicist Guest)]

I would have to say that if anything, these thoughts have intensified. The universe is far stranger than we once thought and far stranger possibly than we can imagine. Why do I say that? Because we live in a universe that is expanding, that is accelerating, that is forming stars, planets, black holes. And it all came from a Almost perfectly smooth, homogeneous, hot. Very, very hot beginning. That's not a story that someone 100 years ago would have told. None of it. So, yeah, strange.

[Neil deGrasse Tyson]

I have books, old books, that describe the universe as an ordered, majestic place. Everything in the right spot, everything in stately orbits around you. And then we found out that things slam into each other, they blow up,

[Mordecai Mark McLow (Astrophysicist Guest)]

it's full of turbulence, chaos.

[Neil deGrasse Tyson]

Yeah, I mean, it's just a mess.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes, thank you for that cogent description of the modern understanding of the universe.

[Comedian/Co-host]

Wait, so can I ask you both a question then? Now you're both in the field of trying to understand the universe better, right? Solving mysteries at some level.

[Neil deGrasse Tyson]

Trying to understand the universe, but better.

[Comedian/Co-host]

I. I guess if like doing a tight ten at the Chuckle Hut in Sheboygan makes solves the universe in any way, I might be in that business. But does it make either of you feel, I don't know, bad that like, the more you study the like, more you find it chaotic? I don't mean I don't.

[Mordecai Mark McLow (Astrophysicist Guest)]

Let's just say it keeps me in a job.

[Neil deGrasse Tyson]

I have a different way to answer that.

[Commercial Narrator]

Yeah.

[Neil deGrasse Tyson]

If the universe were more and more chaotic, requiring equally as complex laws of physics to understand it, then what are we doing? But the real majesty is that it's just a few laws of physics that

[Mordecai Mark McLow (Astrophysicist Guest)]

generate all that chaos in mass, that

[Neil deGrasse Tyson]

generate all that chaos. It's just a few laws of particle physics that account for all the particle zoo that we know and love.

[Mordecai Mark McLow (Astrophysicist Guest)]

Except for dark matter.

[Neil deGrasse Tyson]

Except for dark matter. We're not there yet, but we're working on it. If to understand the universe required a complexity of theorizing that matched it, then all bets are off. I'll just go home, go to the Bahamas, give up on it. But. But if foundational understanding, like Mordecai, you said all this without even mentioning that you're an expert in fluid dynamics.

[Mordecai Mark McLow (Astrophysicist Guest)]

And I implied it by discussing the turbulent dynamo, which is absolutely an extreme fluid dynamics problem. Yes, but fluid dynamics, Magnetized fluid dynamics even.

[Neil deGrasse Tyson]

Look, he had a face. He made a face. He was like, I'm angry. So fluid dynamics is the study of fluids, which can be gaseous or liquid, and kitchen sink, there's a whole set of rules just for fluid dynamics that works in water flowing through pipes, as

[Mordecai Mark McLow (Astrophysicist Guest)]

it does in stars.

[Neil deGrasse Tyson]

In stars. So that is the wild thing that is the majesty of the universe, right?

[Comedian/Co-host]

Cause you're settled on the rules and now you're just like watching to see how these rules play out on a universe basis. And it's Fun.

[Neil deGrasse Tyson]

Yes, yes, yes, we'll go with that.

[Comedian/Co-host]

I get that.

[Mordecai Mark McLow (Astrophysicist Guest)]

We'll go with that.

[Comedian/Co-host]

That's your tight 10 at the Sheboygan Chuckle Hut.

[Mordecai Mark McLow (Astrophysicist Guest)]

Okay, he hasn't spent enough time in Sheboygan.

[Neil deGrasse Tyson]

Neither have I. Mordecai, how will quantum computing help what you're doing?

[Mordecai Mark McLow (Astrophysicist Guest)]

We don't know yet.

[Neil deGrasse Tyson]

Is there a problem that is intractable now that you think will succumb to quantum computers?

[Mordecai Mark McLow (Astrophysicist Guest)]

Well, well, certainly problems in atomic physics, like, say, the million different transitions in the molecule water that all produce different amounts of radiation of different colors, different spectral lines. Those may well be better done by quantum computing than by the poor guy who came from banking into astrophysics and ended up having to do that for his thesis. But. But most of the problems we have, we don't yet know how to compute on a quantum computer. Give it 100 years.

[Comedian/Co-host]

100.

[Neil deGrasse Tyson]

Oh, or 10. I mean, don't we say our brains.

[Comedian/Co-host]

This is.

[Mordecai Mark McLow (Astrophysicist Guest)]

I mean, look, a hundred years ago,

[Neil deGrasse Tyson]

we were only inventing quantum physics.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yes, we had already invented quantum physics. And we're still figuring it out.

[Neil deGrasse Tyson]

Yes, we're still figuring it out.

[Mordecai Mark McLow (Astrophysicist Guest)]

It's.

[Comedian/Co-host]

It took.

[Mordecai Mark McLow (Astrophysicist Guest)]

When Newton wrote down his laws of gravity, it took a century before we could explain the orbit of the moon.

[Neil deGrasse Tyson]

Yeah, yeah. Okay. That's all the time we have. Nagin, thank you for asking those questions. And Mordecai, brilliant answers. Right on, Brand.

[Mordecai Mark McLow (Astrophysicist Guest)]

Well.

[Neil deGrasse Tyson]

And you have some groupies.

[Mordecai Mark McLow (Astrophysicist Guest)]

Are you saying that I'm fusing here?

[Neil deGrasse Tyson]

I'm saying. Plus, you had at least one groupie there who was quoting you chapter and verse from 10 years ago.

[Mordecai Mark McLow (Astrophysicist Guest)]

I was impressed. Thank you.

[Neil deGrasse Tyson]

Yeah. No, our people go back.

[Comedian/Co-host]

Yeah. No, they're like, no things the listeners.

[Mordecai Mark McLow (Astrophysicist Guest)]

Yeah, right. Audience to have.

[Neil deGrasse Tyson]

All right, thank. This might be our first interview with you.

[Mordecai Mark McLow (Astrophysicist Guest)]

This is my first time in this chair.

[Neil deGrasse Tyson]

In that chair. But not your first time in my office.

[Mordecai Mark McLow (Astrophysicist Guest)]

Not the first time in this office.

[Neil deGrasse Tyson]

It works just down the hall. All right, Nagin, not your first rodeo here?

[Comedian/Co-host]

Not my first time.

[Neil deGrasse Tyson]

Deb, look forward to your next time joining us.

[Comedian/Co-host]

Such a great time.

[Neil deGrasse Tyson]

And we'll find you on. Wait, wait, don't tell me you can find me on.

[Comedian/Co-host]

Wait, wait, don't tell me. If you're in Chattanooga, Tennessee, on June 24, you can find me there too, at the Comedy Catch.

[Neil deGrasse Tyson]

Oh, Chattanooga, Tennessee. We'll look for you. And that's June 24th.

[Comedian/Co-host]

June 24th, I'll be doing the Muslims Are Coming with equally threatening friends. A night of standup comedy.

[Neil deGrasse Tyson]

Okay, will that attract people or scare people away. If no one shows up in Chattanooga, Tennessee, we'll know why.

[Comedian/Co-host]

I need Dr. Maglo to do a simulation and see what happens.

[Neil deGrasse Tyson]

That's all the time we have. So again, Mordecai, thank you.

[Mordecai Mark McLow (Astrophysicist Guest)]

You're very welcome.

[Neil deGrasse Tyson]

Thank you.

[Mordecai Mark McLow (Astrophysicist Guest)]

Great fun to be here.

[Neil deGrasse Tyson]

This has been Star Cosmic Queries on the Formation of Planets with my friend and colleague, Mordecai Mark Macklow. Until next time, keep looking up.

[Commercial Narrator]

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[Capella University Announcer]

There's a fire inside you you can't ignore. Stand still. Not a chance. You're a lifelong learner who's come this far. Now we're here to help you keep going.

[Commercial Narrator]

Further.

[Capella University Announcer]

Capella University. What can't you do? Visit Capella. Edu to learn more.