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Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk. I'm Neil deGrasse Tyson, your host. I'm an astrophysicist with the American Museum of Natural History right here in...
Welcome to StarTalk, your place in the universe where science and pop culture collide.
StarTalk begins right now.
This is StarTalk.
I'm Neil deGrasse Tyson, your host.
I'm an astrophysicist with the American Museum of Natural History right here in New York City.
Where I am now and across from me, across from my recording table is Chuck Nice.
Hey, Neil.
Chuck.
How are you, buddy?
Welcome back to StarTalk.
Thank you, sir.
Love having you.
And I love being here.
This is a Cosmic Queries edition.
Did they tell you that before you came in?
No, they didn't, but you know that's one of my favorite things is the Cosmic Queries.
Cosmic Queries, we pick a topic and we solicit input from the listeners and fan base and they write in questions.
I don't read the questions in advance.
That's correct.
But they're handed over to you.
That's right.
You pick and choose.
That's right.
And if I don't know, I'll just say, I don't know.
There it is, go on to the next one.
Which by the way has never happened.
Actually, it's never happened.
Thus far.
You know what it is?
It's not that I, because there are answers I didn't know but I gave a different answer to something else.
That's how I did it, right.
You should run for office.
And so I think that, so the topic here, the topic here is Cosmos.
Right.
Not the Cosmos, but Cosmos.
Exactly.
The show.
The show.
Because I had something to do with the show, right?
You had a little something to do with the show.
I hosted the show.
That's right.
So, I mean, we had 100,000 zillion other people working on it.
We have writers and producers and.
Animators.
And gaffers.
Gaffers.
So, these are all on Cosmos.
And we have in studio, briefly, I don't think we have them for the whole show.
We have Steven Soter, my friend and colleague and co-writer of Cosmos along with Andrew.
And Steve, thanks for coming in.
Thank you, Neil.
So, and by the way, he co-wrote the original Cosmos.
So, if any question comes up from back there, I'm going to him.
Awesome.
All right.
Fantastic.
So, what do you have?
You want to jump right into this?
All right, let's go to our first from email.
And this is Nicholas Brody.
I won't give your email address, Nicholas.
Here's his question.
I have a question for Dr.
Tyson.
I figured that because you wouldn't have a question for me there, Nicholas.
And it is StarTalk Radio.
It is StarTalk Radio.
It is my show.
That's right.
I finally got the chance to see the first episode of Cosmos and I loved it.
I noticed though that when the ship was traveling through the rings, there was a disturbance in the rings from the passage.
However, at Mars and Venus, there were no atmospheric effects shown.
Even though the ship was clearly in the atmosphere, was this a deliberate oversight?
These people are carrying on like the way I do when I look at stuff.
Yeah.
You know, I get all on their people's cases.
So I don't want to defend what may have been an oversight in the illustration and in the animation and in the visualizations, but what is sure is that we focus on portraying what is visually accurate, anything we are describing.
Okay, that's where the true focus of this exercise is.
So there are other visuals that may be sort of visually enhanced just so that they make the journey a little more fun.
The best example here is we went through the asteroid belt and they were like, the asteroids were kind of all over the place there, and then they're not that close to one another in the actual asteroid belt.
The voyager would have been toast had it gone if the asteroid belt was as portrayed.
But we didn't have a conversation about how things are, rocks are distributed in the asteroid belt.
So we just wanted to convey, we're going through the asteroid belt now, check it out.
That's all that was.
We landed at the Oort cloud, a repository of comets in the outer solar system, described as comets far enough apart that they're as far away from one another as Earth is from Saturn.
That's empty.
And so this was conveyed and talked about in great detail.
So, but on Venus, we did show that the atmosphere looks different because of how high the air pressure is on Venus.
The refraction is different on Venus than it is here on Earth.
And it looks like you're in a bowl.
So we showed that in the visualizations.
So some, there is, I shall say, some literary leeway or license.
Yeah, some literary latitude.
Latitude.
Keep alliterating there, yeah.
Literary license and latitude.
No, so, but what we describe is the real running theme of the show.
Right.
And that is tight.
As tight as we think we've made it.
As tight as we can make it.
That's right.
But then other things.
And by the way, and at the end of the day, it is the ship of the imagination.
So if it doesn't leave a wake through the atmosphere, you know, you can chill out on that.
How convenient.
Steve, the ship of the imagination was in the original cosmos.
And but we totally re-envisioned it for this one.
Were you happy with the original rendering of it?
I never liked the one in the original series.
But I love the present one.
You love the present one, okay.
You said the right, you gave the right answer there.
There you go, Nicholas.
There's your answer.
So.
The ship goes a lot of places without messing up the environment.
Right, there you go.
All right, cool.
I gotta tell you, he's a very detailed guy, this Nicholas.
He was on every little minutia.
Let's move on to Amy also emailing a question in.
And her question is about Arabic numbers.
Mr.
Tyson, hey, Amy, that's Dr.
Tyson to you.
No, it's Dr.
Tyson to you.
Oh, that's true.
It's Neil to Amy.
I was just watching the latest episode of Cosmos.
Love it.
And you mentioned Arabic numerals and the concept of zero.
This got me to thinking.
I've often heard of math being a universal language, but would an alien civilization use a base of 10?
What if they had 12 fingers, for example?
If we counted in a different way, would pi be rational?
Is our method of math a universal truth?
Thanks.
Ooh, Steve, why don't you kick in on that?
Well, there was a base 12 number system.
It's one of the oldest.
And it's almost certain that aliens with different numbers of digits would have a different base number for the counting system.
In fact, the base 12 was Babylonian, right?
That's why clocks had 12 hours.
12 is really more convenient in some ways because it's divisible by three, four and two.
Whereas 10 has only been.
And by, yeah, two, three, four and six.
Makes sense, I never thought of that.
But in any numbers.
So you can talk about a quarter of an hour, a third of an hour.
Yeah, exactly, yeah.
But the number pi, the ratio of the circumference to the diameter of a circle, would be an irrational number, an infinite fraction.
No matter how many fingers you have.
In any system.
In any system.
Gotcha.
So now.
So all the irrational numbers stay irrational.
Stay irrational.
There's no hope for them.
Wait, wait, Steve, suppose we went in base pi.
I can't even imagine that.
I don't think it's very practical.
Yeah, but then pi would be equal to one or something, or 10, right?
You count in pis.
I hope they're blueberry, because you guys have lost me.
You have lost me.
No, because base 10 is we have 10 numerals, zero through nine, and when you run out of numerals, you start combining them.
You get to nine, you go one, zero, one, one, one, two, one, one.
So that's how you would count in any base.
So base pi, pi would be the unit.
The unit.
The unit is pi.
Is pi.
And so you count in base four, would be one, two, zero, one, two, three, one, zero, one, two, one, three.
Our integers would all be irrational.
We have irrational integers, I think.
It'd be a mess.
It'd be a mess.
When we come back, we are in Cosmic Queries mode.
Everything about Cosmos, the TV series, we'll be right back.
StarTalk Radio, Cosmic Queries edition.
I like to think of it as StarTalk after hours.
Come and bring your questions.
We call them from the internet, all of our social media outlets, email, Twitter, our website, and we ask you, do you have any questions about Cosmos?
Yes.
Not the Cosmos, because we'll take those anytime, but Cosmos the show.
The show.
That's right, appearing on Fox and on National Geographic.
And so Chuck, you've got the questions.
I have the questions, which you have not seen.
I've not seen, and I have in studio as a special guest, one of the co-writers of Cosmos, Steven Soter.
Steve, thanks for being on StarTalk.
Thank you.
All right, let's go for it.
All right, let's move on to our next question, and this one is coming from Joe Trow.
And Joe says, in Cosmos, you recently suggested that the furthest mapped galaxy was among the first galaxies to be formed.
I'm curious as to why that is thought to be so.
If more distant galaxies exist and their light hasn't reached us yet, how can we be sure galaxies from 13.4 billion years ago were indeed the first galaxies to be formed?
Ooh, he is throwing down a gauntlet.
Throw down.
That's good stuff.
That's some good stuff.
Okay, so here's the thing.
There are galaxies whose light haven't yet to reach us.
He's wondering, could they be older than that galaxy?
That's what he's wondering.
That's what he's saying.
Okay, so there's a problem in how we talk about the early universe that I have to clarify.
It's not a problem.
It's a lexicon problem, right?
So when we say we look so far back in time, we see galaxies forming, we are seeing a galaxy in the act of forming, okay?
Somebody on that galaxy today looking in our direction, and we'll see the Milky Way forming, all right?
And so all the galaxies were forming at about the same time in the early universe.
And so when you have a window to the early universe, as you look out in space, we look back in time.
The universe is a great time machine because light takes time to reach us.
We're seeing an epoch in the universe when galaxies were forming.
So we just say we are seeing the youngest galaxy that our telescopes have yet to find.
And there'll be others, but all the galaxies in our current universe looked like that back then.
So maybe we shouldn't say it is the single oldest galaxy.
I mean, I think that's, would you agree, Steve?
We're saying it the wrong way.
Well, if you were to wait a few billion years, you would see galaxies forming that many more billions of light years away from us, but they all still formed at the same time in the past.
So there's a distinction between.
You get that, Chuck, wait a few billion years and you'll see this.
Wait a few billion years.
Listen, I got nothing but time.
I think I got a gig next June.
Other than that, I'm good.
Right, so in a billion years, that freshly born galaxy is now a billion years old and now we see another billion light years farther away and we see that galaxy being born.
But they all were born at the same actual time.
And that is because there was, that's because there's a singularity that created this.
Correct.
Correct.
Gotcha.
So it doesn't make a difference because the singularity will be the same.
That's the constant.
For everybody.
For everybody.
Everybody, you got it, Chuck.
Right.
Thanks for helping us answer that question, Chuck.
You know, I'm feeling kind of good about myself right now.
You go back and tell your sixth grade teacher, yeah, I didn't do good in science later on.
All right.
Actually, I'll be my eighth grade teacher and he would be so jealous of me right now.
Oh.
Yes, he would.
Mr.
McNeil, F you.
No, I'm joking.
No, he was a great guy.
Let's move on.
This is from Justin Brickell.
Okay, subject matter, black holes.
All right, here we go.
On the last episode of Cosmos, we saw an X-ray image of a black hole.
If the gravity of the black hole does not allow light to escape, then why can we see X-rays from black holes?
Aren't X-rays light waves?
And I'm gonna tell you right now, I am so excited about this question because this is a great question and I really don't know the answer.
And you didn't think of it at the time you saw that episode.
Well, you're not really seeing the light coming from inside the black hole.
You're seeing the light coming from a disc of material which is spiraling into the black hole and that is allowed to escape.
Yeah, so it's not in the black hole yet.
It's not in that black hole yet.
It's the last cry of matter that has been heated to such high temperatures.
It's the death cry.
It's the last gasp of matter in its death spiral which has been heated to so high temperatures, it emits.
You know, out of your stove, you turn it on and it glows red hot.
Right.
You say red hot is hot, it can glow hotter than that.
Got you.
It can glow white hot.
White hot.
Blue hot.
Blue hot.
But then it melts, but it can still glow and it glows so hot that it can be glowing in X-rays.
And so this is glowing matter at just, I'm coming to find me, Matilda, and then it's gone.
Oh my gosh, so it's not in the black hole, it's just heated where it becomes X-ray.
X-ray light becomes copiously emitted.
So it's the Fred Sanford of material before it is.
Elizabeth, I'm coming to join you, honey.
That's it.
That's it.
So that's what it is.
You're too young to remember Fred Sanford and Sanford and Son.
Elizabeth, yeah, it's the last bit.
It's the last bit.
Oh man, that is fascinating stuff.
Excellent, excellent.
All right, let's move on.
This is from Laura Nugent.
Laura wants to know about light years, guys.
Is this email?
You got this?
This is an email, sorry.
This is an email from Laura.
Laura says, I was watching the latest episode of Cosmos.
A sky full of ghosts and had a question.
I understand that every time we look at the night sky, we are looking into the past.
I also note that a light year is the distance light will travel in one year.
What I would like to know is, how are light years calculated?
For example, how do we calculate that the center of the Milky Way is approximately 30,000 light years?
Is it some sort of triangulation?
Steve, you wanna get that?
It begins with triangulation, yes.
We determine the distances to the nearest stars by basically triangulation.
And then when we knew how far away those stars were, we learned something about stars themselves and how luminous stars of different kinds are, which is depending on their particular spectrum, the kind of light they put out.
And then when we could see those same kind of spectra in other more distant stars too far away to measure by triangulation, we would know how far away they were by how bright they appeared to be and so on.
So it was a kind of bootstrapping operation to extend these distances eventually to know how far away the center of our galaxy was and then to recognize individual bright stars in other galaxies to then determine how far away those galaxies are.
Hubbell did that first, the man, Hubbell the man in the 1920s, yeah.
But it did begin with triangulation.
And by the way, it's a huge effort.
It's called the distance ladder.
In fact, if you Google distance ladder, you'll get a whole web wiki page on it.
And it was a major triumph of 20th century astrophysics.
And it was many people working in consort, even competitively, trying to get the distance scale of the universe, the yardstick of the universe.
And it wasn't much reported on in the news because there was no eureka moment burning a midnight oil overnight.
It was just this long drawn out effort to find out how far away things are in the universe.
Just to be able to calculate distance and that's it.
Exactly, exactly.
So she picked up on one of the greatest challenges of 20th century astrophysics.
But we got that and we're on to the next problems, yeah.
Okay, so now, gosh, very quickly, here's my follow up question.
Has there ever been an anomaly that would create the appearance of a brighter star, longer distance, but it actually wasn't?
Well, there was a set of observations of galaxies sitting right next to one another.
And one, you use the same method of distance calculation and you get two very different distances for these two galaxies that look clearly right, one right next to one another.
And so this would be the anomalies in the distance scale.
There was a professor at Caltech named Halton Arp, Chip Arp was his name, who was a big proponent of these anomalous cases.
And closer scrutiny would ultimately reveal that these pairings of galaxies were just line of sight juxtapositions, that they were not actually interacting with one another.
The claim is though that some of them may be interacting with each other.
I'm not certain that this is solved yet.
Oh, controversy abounds.
Oh, that's pretty awesome.
Okay, okay, well thank you.
Steve is always for the underdog.
All right, I think we have time for one more.
All right.
A quick one.
Here's a quick one.
This is from Trevor Bradley, also by email, and Dark Matter Dyson Spheres.
I had an idea one day that all the dark matter in the universe is actually Dyson Spheres, and all the aliens are hiding inside of them.
I'm glad I picked this one for last, okay?
While I think this makes for good science fiction, I suspect it isn't true.
What do we know about the distribution of dark matter in the galaxy?
So in the 20 seconds left in this segment, you want me to give the full exposition of Dyson Spheres and whether dark matter is hiding out within them with aliens.
All right, so we're gonna have to pick that up after the break.
After the break, are you okay with that, Chuck?
No, I'm okay with that.
You can Steve, you're okay with that?
All right, all right.
When we come back, more of StarTalk Cosmic Queries.
Cosmos.
We're back, StarTalk Cosmic Queries Edition, the Cosmos, the Cosmos TV series.
Yes.
A little self-serving, because I'm host of the series, Chucks.
I feel awkward in this.
I don't know why.
I don't know, I just feel.
There's no reason to feel.
It's a fantastic show, you're a great host.
There's nothing wrong with that.
Thank you, and who gives you paychecks here?
I believe that would be you.
Funny how that works out.
Just a disclosure here, yes, Chuck is paid for his appearances on StarTalk.
That's so funny.
So, we left off talking about.
Dyson spheres.
Dyson spheres, yeah, yeah.
So there's a colleague of mine, Freeman Dyson, a rather senior physicist, who had thoughts that if you were an advanced civilization, you would need energy, more energy than perhaps your home planet could support on its own.
So then you go to your home star.
Well, how much star energy are you gonna get?
Only the energy that's sort of headed your way.
Correct.
The star is illuminating other planets, but if you were greedy, if you were just overcome with greed, you would say, I want every photon emitted from that star.
And you'd build a sphere around that star to capture all the light and channel all that light to your planet.
That's what you would do.
And whether or not you approve this with your neighbors on planets exterior to you, because then you would be snuffing out their.
Their light would be gone.
Their light would be gone.
Yeah.
So if you now control that much energy, you could have an awesome civilization, it is imagined.
You'd be the Mr.
Burns of your solar system.
It is.
And so you wonder, are these aliens in Dyson spheres closing off the existence of matter, and could this be all the dark matter in the galaxy?
And I, no, no.
Because that sphere will actually still radiate.
There's no such thing as a free lunch.
You can't take energy away and not have it come out in another form.
Gotcha.
And that sphere would heat up, and it would glow and have a kind of infrared glow.
It wouldn't glow visibly.
It would glow invisibly in infrared.
And so you'd see, we'd see that with infrared telescopes, and we don't.
Plus, there's good reason to think that the dark matter is not made of ordinary matter at all.
That it's something that remains mysterious, but is nothing that we know.
Like electrons, protons, neutrons.
So if you put in dark matter as electrons, protons, and neutrons in the Big Bang models, you don't get the universe that we currently live in.
Well, there you have it.
So we're good on this.
All right.
Well, that makes perfect sense.
All right, Chuck, what else you got?
All right, let's move on to a question from a nine-year-old fan is what this says.
Does that mean the person's been a fan for nine years?
No, it means that she is indeed nine years of age.
Nine years of age, that's how old I was when I discovered the universe, or rather, the universe discovered me.
There you have it.
I was called by the universe.
Okay, go on.
Zoe Bales.
Okay, it's her name.
You're gonna imitate a nine-year-old girl.
Come on, I gotta give it to you.
Hi, my name is Zoe, and I'm, wait for it, nine years old.
I'm your biggest fan in the universe.
I was a fan before your TV show.
I watch Cosmos all the time, by the way.
I listen to StarTalk Radio in the car with my mom, and when I grow up, I want to be just like you.
In fact, in February, I wrote a report about you for Black History Month.
Anyway, I have two questions.
One, you said the most meteorites are only as big as blueberries.
How come they look so big in the sky?
Ooh.
Two.
Two questions.
How come space is a vacuum?
Why isn't there any oxygen or anything else?
That's all I have for now, but you'll be hearing from me.
That sounded like a threat.
You'll be, don't diss me on this one.
But you'll be hearing from me.
I'm gonna be old in a nursing home.
Remember me, Zoe?
You dissed my questions.
All right, so one of them was, how come space is a vacuum?
Well, all the air that would be in space is attracted by gravity, so it falls down to the surfaces of planets.
And so it's really just gravity.
It's just gravity.
That's all there is.
That's it.
And as you go higher up in the atmosphere, the air gets thinner and thinner.
They aren't thinner because there's less, well, you're further and further away.
Well, yeah, so all the air is crammed and compressed down right near the Earth's surface.
So by the way, the thickness of our atmosphere is to Earth what the skin of an apple is to an apple.
Yeah, so the gravity is really squeezing this stuff down.
So most of the universe is a vacuum.
So the saying, nature abhors a vacuum, that's just false.
Nature did love it itself some vacuum.
If that means you've never been in space, if you say nature abhors a vacuum, because on Earth, there's so much pressure in the air, if you try to take away the air, air's gonna try to fight you on it.
Oh, by the way, that's why it's hard to pick up a suction cup.
It's not because it's sucking itself down, it's because the weight of the atmosphere is pressing down on the rubber.
Because you removed.
You removed the air that would balance it.
From the inside that would balance it out.
So it's not, there's no suction.
We call it suction.
It's just the weight of the atmosphere is leaning on it.
Right, so there's nothing pushing back.
So to balance it out, you got it.
And the other question was what?
The other question was, you said.
Oh, yeah, yeah, so.
Most meteorites.
So it's meteors, most meteors.
These are the things that are rendered to glow moving through the atmosphere.
They're about the size of a blueberry.
Yeah, oh yeah.
And you said, well, how do they look so big?
Because they're moving fast.
And you know, tens of thousands of miles an hour and all that energy, where does it go?
It heats up and it can vaporize the meteor.
It could render the atmosphere glow.
And so what you see is the glowing trail of this moving blueberry.
It's all a light show, Zoe.
It's all a light show.
All a light show.
Now, the bigger ones come through and if they're big enough, they won't burn up and they hit the ground, then they're a meteorite.
Gotcha.
And you don't want to be where it fell.
Because that would be the end of you, Zoe.
And we need you to come back and be my nemesis later on.
We gotta run.
Just for this segment, we'll be back with more Cosmic Queries on The Cosmos.
We're back, StarTalk, Cosmic Queries edition.
Chuck Nice.
The question deliverer.
Correct, sir.
Go for it, man.
Here we go, this is from Matt Stroderd.
All About Cosmos.
All About Cosmos, the series.
Which you are the host, by the way, in case you didn't know.
Thanks for that plug.
I needed that plug, yeah.
All right, Matt wants to know about singularity and subatomic particles, okay?
I recently watched and thoroughly enjoyed the latest episode of Cosmos, as I have the previous episodes.
I had not considered the possibility of multiple universes on what you described within a black hole.
This raises the question of how does this theory fit with singularities as well as what happens on the atomic level in a black hole?
Does quantum physics still obey the same laws inside of a black hole?
By the way, I put the inside part.
This is a brilliant question.
So if you look at what we call classical relativity, so relativity without quantum physics, and you do the space-time diagrams for what happens inside of a black hole, there's a way, there's a trajectory you can plot for yourself through a black hole where you will end up in another space-time.
And that is what we portrayed in the series.
And we didn't know how to draw it because no one's ever been there to come back out and tell us about it.
So we just imagined going into whole other universes that are there.
Whole other space-times are allowed inside of black holes.
No doubt about it.
Well, let's put it another way.
The general relativity equations have been accurate for everything else they've predicted that we've been able to test.
So we're not given reason to think that they're all of a sudden wrong when they say there's a whole new space-time that can open up inside a black hole.
Why think it would be wrong there, but right everywhere else?
So that's why we give it some confidence.
However, what we don't know is the day we marry general relativity to quantum physics, because quantum physics is the science of the small, and general relativity is the science of the large, and they never really had to talk to one another.
But when is the large small?
At the center of a black hole, when whatever was the progenitor became little.
And now you have big things being little.
Same problem is at the Big Bang itself, where the whole universe was small.
So, there's some kind of shotgun wedding going on there.
We don't know exactly what, and we don't know who's gonna win.
Whether there's a third theory you need that encompasses the both of those, or whether quantum physics absorbs general relativity, we don't know.
Only when that comes out, will we be able to say with certainty, or with much higher confidence, whether this space time is real, or whether some quantum phenomenon kicks in, preventing it.
So he asked me exactly the right question.
Let me follow you here.
We may have, indeed, once you marry these two, different laws of physics.
They may be created by this shotgun wedding you talk about.
Yes, no, I mean some new understanding of nature that supersedes both of those two.
I gotcha.
Now we've done that before.
We've had, in other ways, they use magnetism and electricity, and we found, hey, these are the same thing.
Right.
But under a larger umbrella that we call electromagnetism.
Exactly, yes.
That word is two concepts stapled together in the 19th century when we discovered that they're the same phenomenon.
Wow.
So, yeah, yeah, that was a great question.
Matt, you are a very astute young man.
You had that question, too, when you were watching Cosmos.
I certainly did.
Exactly.
Because Matt emailed me.
He said, let me try Chuck first, because this is so easy.
I chuckle at it.
All right, let's get to this one very quickly.
Metric expansion of space from Oliver Snell, and Oliver is emailing us.
Okay, I was watching Cosmos, and it was so amazing.
I spent the entire following day reading about the universe, galaxies, black holes, and the local group.
As it should be.
That's right.
And the metric expansion of space.
Here's my problem.
I wasn't ready for how depressing the metric expansion of space is.
The idea that eventually everything in the universe that is not in the Milky Way's gravitational range will be unobservable is terrifying and sad.
Do you have the same thoughts?
If so, how do you deal with that fact?
Okay, on our website, we'll put a list of counselors for you.
We need a metric expansion of space hotline.
In the accelerated expansion of space, there will come a day where all galaxies will have expanded beyond our visual horizon.
We'll look beyond our galaxy and there'll be nothing there.
Everything we currently know and accept and love about cosmology, that book will have been discarded because there'll be no evidence that there was ever a past in the cosmos.
Because we get the information about the past by looking at galaxies from long ago.
If you were born into that world, you would be reading a book of the universe with a chapter missing and you would not even know it was missing.
Wow, that is a world I don't wanna live in.
No, what, well, maybe you already are.
And there are chapters missing from this universe.
That makes sense.
And that you have yet to consider its impact on how we now think about how the universe works.
When we come back, more Cosmic Queries.
We're back, Cosmic Queries, StarTalk.
That last question, he wondered if I had some kind of existential angst about the expansion of the universe.
How do you deal with it?
Accelerating the galaxies out of our horizon, leaving just the Milky Way, a merged Milky Way andromeda system.
How do I deal with it?
Yeah, I try not to invest emotions in the universe, and I say, isn't that awesome?
That there will be a future time where we won't even have cosmology because we won't even have any access to the history of the cosmos.
That's just kind of interesting.
That is.
And it makes me wonder today, like I said, is there any chapters ripped from our book that we are currently reading to understand or inventing and writing to understand the nature of the universe?
So it's all cool for me.
Fantastic.
Yeah, but now we are in the lightning round.
Yes, it is, my friend.
Test the bell.
There it is.
There it is.
I will give speedo answers to your speedo questions.
All right, ready, go.
Here we go.
This is from Adam, and Adam is emailing in about the moon.
Neil, in Cosmos, you said the moon coalesced from debris.
I thought I heard you say before that it formed from a Mars-sized impact event.
I heard that theory before, just not sure if I heard it from you.
By the way, love the conversation with God.
Oh, that was the earlier episode.
Interesting, thanks for that God plug.
Yes, in the show, in Cosmos, we showed the impact of the Mars-sized object that then made the debris that coalesced to form the moon.
So go back and find it, you'll see.
And so yes, there's still a Mars-sized object colliding with the moon.
Most of that continuous mass goes away, but there's a hell of a lot of debris, mostly from Earth's crust, that formed the moon.
The moon is made of largely Earth's crust.
Next.
That's why it has very little iron in it.
Most of the iron in the Earth is in the center of the Earth, having fallen there for weighing so much more than the rocks that floated to the top.
Go.
Now a double answer.
This from Christopher Fletcher, and Christopher wants to know about the Cosmic Calendar.
I think the Cosmic Calendar is a great idea for lending the scope of deep time to history as we know it.
But is there some version of this concept that uses the quote unquote end of the universe as the final date with heat death as midnight, December 31st?
Or are there estimations of such a far future going up in the end and having the current moment something absurd like the first fraction of a second January 1st?
All right, so here we go.
There's a book called The Five Ages of the Universe.
Check it out, okay?
I might have even written a blurb for that book.
Sweet.
And in that book, written by a colleague of mine, that book talks about the death of the universe.
And it is in 10 to the 100 years from now, or more.
Okay, I'm fine now.
No, so a Google years from now, that is so far away, it just doesn't make sense to start making calendars out of it.
Gotcha.
So there you go.
There you go.
Okay, this one is from Alex Dolan.
Alex wants to know this.
Hi Neil, every model of our solar system I've seen shows all the planets orbiting basically on the same plane.
Why is this the case and not something closer resembling a model of an atom with many planes, so like electrons in an atom?
This is the famous nebular hypothesis that first came out in the mid 1700s.
Laplace and Kant, both independently, they may have heard of each other's work, but they both, brilliant people, came up with the idea that you start with a gas cloud that started spinning while it's collapsing.
If you spin while you collapse, you make a disk.
And if all the stuff you make is made in that disk, everybody's orbiting in the same plane, in the same direction.
And it's the Oort Cloud of Comets that surrounds us entirely that tells us that the Oort Cloud did not participate in that collapse.
It's what's left over after you collapse the pancake and make your planets and moons and the star in the center.
Got it, go.
Bang, that was great.
Okay, Neve Rav Bansali.
Neve wants to know about faster than the speed of light.
Dr.
Tyson, regards.
I'm writing from Royal Oak, X-ray.
Can the inner-
Well, I'm writing from, I wanna know where the people came from.
Royal Oak, Michigan.
Okay, fine.
Okay, can the energy of a supernova increase with the speed at which photons travel from the star, thus essentially increasing the speed of light?
No, no, it's just an explosion.
Matter comes out.
Light will always move at the speed of light.
No violations of anything, of any known laws of physics there, but it's nonetheless quite the spectacle in the cosmos.
All right, next.
Boom, all right, Pat Hickey wants to know about the origins of life.
Pat emails in and says this.
So do I.
Next question.
No, what about the origins of life?
All right, go quick.
In the news cosmos, you say our humanities journey started at 9.45 on New Year's Eve.
What do you think the earliest realistic time that advanced life could have evolved on another planet after the Big Bang, given perfect conditions?
No, so the point is if Earth was born at the time of the Big Bang, the universe would have had life as we know it as early as a billion years after the universe formed.
But we had to wait until enough heavy elements were formed, the kind of elements that make life and that make planets, and that was not formed in the Big Bang.
Big Bang was pure hydrogen, helium, trace amounts of lithium.
What are you made of?
Carbon, nitrogen, oxygen.
You get that from inside of stars that had to be born, die, spread their guts everywhere and rich, make the life later on.
So here's the thing.
What you want to do is form complex, intelligent life earlier on a planet, because Earth was really slow about making that happen.
And still is.
Still making it.
So that would have been cool.
If intelligence was this moving force, how intelligent would we have been had we evolved earlier ago as complex life than just a couple of million years?
I mean, forget about it.
I don't know if we have time.
We don't have no more time for another question.
I get the answer to it.
Love, Dr.
Exploration about artificial selection of dogs on Cosmos.
If we had a couple of millennia to spare, would we be walking cats, getting them to fetch?
Oh, you want to breed cats to fetch?
Yes, can we do it?
No, we have a cat that fetches.
It's called a dog.
All right.
You've been listening to StarTalk Radio Cosmic Queries edition, Cosmos.
Chuck, thanks for being on with me.
My pleasure.
Thanks earlier.
We had Steve Soder, my colleague, in earlier segments helping me out answering these questions.
Until next time, I bid you to keep looking up.
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