Cosmic Queries – Why Are We Here?

What I do every time I’m out and I have my laser, I flash it at a star that’s in the night sky, like a pulse, and then I turn it on.

So there’s a length of light.

So if you leave the light on for one second, there’s a beam that’s 186,000 miles long.

Right.

Okay?

And so that is on its way to that star, and maybe to a planet.

That is so cool.

Yeah, so it’s my space graffiti.

There you go.

I’d say Neil is here.

Welcome to StarTalk, your place in the universe where science and pop culture collide.

StarTalk begins right now.

This is StarTalk Cosmic Queries, fan favorite Cosmic Queries.

And this is the Grab Bag edition.

Chuck, you ready for it?

Always loving a Grab Bag.

Yeah, yeah, the Grab Bags are fun because they’re just, they’re like, it’s random.

They just dance around.

That’s it.

And they keep me on my toes.

I haven’t seen these questions, so.

They have the random beauty of a snowfall.

I don’t know what that means at all.

It means you never know what you’re gonna get, but you know it’s gonna snow.

Is that your attempted poetry?

Okay, you got a C plus on that one.

All right, all right, give them to me, Chuck.

Let’s go right in.

All right, here we go.

Now this is Bjorn Furunop who says, Dear Dr.

Tyson and Lord Nice, because you asked for profound questions.

Did I ask one?

No, I did not ask for profound questions.

What for profound questions?

What?

All right, I bring it on.

Maybe I did.

Bring it on.

You never impugned the questions no matter how they come in, what they ask, you treat every question with dignity as if it were worthy of being answered.

Yes, because they are, not as if.

It’s because they are.

I know what I said.

All right, give it to me.

All right, he says, we seem to focus for obvious reasons on the what and the how of the universe.

The why never seems to get much scientific attention because it assumes, I imagine, that there is a purpose, which physics does not really need.

With that in mind, is not the why an important factor for human curiosity?

And should we not then seek to not necessarily find a reason for the universe, but encourage those who seek purpose and thus understanding, okay.

It’s philosophical in nature.

At this time of the morning?

I know, he went, you know, hey.

So you don’t need a why, is what he’s saying, but shouldn’t we still ask why?

So I have a response for that.

I’ve thought deeply about this, by the way.

All right.

I know you have.

In physics, we declare full understanding of something when we can account for all the behavior we’ve seen at Exhibit and predict all future behavior that it might undergo.

And we know what it’ll do when we poke it, when we heat it, when we freeze it.

We say, we understand this thing.

I know what you did last time.

I know what you will do.

So let’s take gravity for an example, okay?

So you can say, well, what is gravity?

How does gravity work?

And then you say, well, why is gravity?

You can go in this sequence, I suppose.

And I’m here to tell you that we can launch space probes from Earth, a moving target, and hit a moonlit around an asteroid, point blank, having sent a space probe to where it would be when they both got to the same point at the same time.

Yes, it is rocket science.

Yes, it is involved a precise understanding of gravity.

If you want to try to now understand why, why did the spacecraft hit its target?

Because we did the calculations and we gave it the right acceleration, and we knew where the target was when it was going to get there.

That’s why it hit.

No, but I love that joke, by the way.

Why did the, nevermind, I’m sorry.

Why the asteroid crossed the road?

Well, yeah, because the way you said it was like, why did the chicken cross the road?

And then your answer was, because we did the calculations and we saw exactly where it was going to hit.

My favorite answer to why did the chicken cross the road is, can’t a chicken cross the road without having its motives questioned every time?

Okay, let me give you the blood version of that.

Why did the chicken cross the road?

Why are you in my business?

So, the point is, you can say, let’s say, the pie is up on a table and it falls to the ground.

You say, why did the pie fall to the ground?

And I can say, well, cause you pushed it.

That should be sufficient response to that why question.

Well, you pushed it, but there’s a little more going on.

If we were floating in space and you pushed it, it wouldn’t fall at all at all because there’s no net gravity vector there that will have the thing fall.

It’ll just, we had to free fall.

It’ll just float.

So, there are plenty of questions where the why is a completely satisfactory answer.

We can give you a why for it.

Why were you T-boned at the intersection?

Because you ran the lights.

There’s no end of questions for which the why, there’s no end of situations for which the why question has a completely legitimate answer that we’re all satisfied with.

Right.

It becomes an issue if you try to get, take a philosophical step and then try to explore why as the consequence of intent.

Gotcha.

In so doing, you are handing intent to things that might have no intent at all.

And therefore you are forcing an intent where there might not have otherwise been one.

And therefore you’re forcing an answer.

And now you’re chasing ghosts at that point.

Right.

Right, right, and he answered his question and you just confirmed it.

He said, it’s not necessary.

So basically what you’re saying is, for the purposes of science, if what we’re really concerned about is science, we don’t need that.

Well, or I have answers that are science that are satisfactory answers to the question one.

That are satisfactory, right.

And I should have said that too.

I don’t need to go beyond that because the science has been satisfied.

You’re satisfied because I have a scientific answer for why something happened.

Okay.

Why is warming?

Because we are adding greenhouse gases to the chemical mixture of the atmosphere.

That is a completely contained answer to the question why.

And why, so I will not cede the accusation that science is not about why.

I will not say that.

There are plenty of why questions where we are all completely content with the scientific answer for it.

Right.

And so there you go.

And like you said, going beyond that, you’re creating a dragon and then-

You created the dragon, correct.

Right.

You created the dragon and now you’re chasing the dragon.

And you want to give meaning and significance to the existence of the dragon you created where there was never a dragon there to begin with.

There you go.

Well, look at that, Bjorn.

You started off by saying that you were gonna ask a profound question.

I gotta give it to you.

But what I do want to say is, because one of them is what is the meaning of life?

That’s not a why question, that’s a what.

That’s not why.

And I might say meaning is what you make of it, given that you have power over objects and events and things and places and people in your influence.

You can create meaning rather than just simply look for it.

Most people are looking for meaning like it’s under a rock or behind a tree, and then they spend their whole lives in search of meaning.

And I’m saying, make the meaning and derive your meaning from that.

Now you might say, why should we have meaning in life?

I would say in our experience, people with more meaning in the life lead a more fulfilled life.

And to be fulfilled is in our short time on earth, maybe something we should all seek so you can have a better time.

Why do you want a better time?

You could keep doing this, but I would ask you, what is the end game of that?

Where will you be satisfied with your sequence of asking why?

Because if you’re never satisfied, then you’re not useful on the moving frontier of science where we can land a target moving in space, where we can take pictures of the early universe in a telescope parked a million miles in orbit around earth, a million miles from earth, called the James Webb Space Telescope.

While you’re asking questions, we are answering questions.

While you’re asking why questions in the dragon that you just created, we are answering questions and advancing civilization.

So, yes, I am discounting many people who are asking why about many things.

But so many other things where you ask a why, the answer when drawn from science or even from culture or whatever, is a perfectly satisfactory answer that no one would further question.

Well, there you have it.

That was very, very necessary.

All of that that you just said, very, very necessary.

I mean, it speaks to so many other things than just this question from Bjorn.

Yeah, it does.

There’s so many other things.

It stretches beyond the limits of the question itself.

Yes.

Wonderful.

Okay, here we go.

Here we go.

Let’s go to our next one, which is J Salmon.

Or is it Salmon?

I don’t know.

I don’t know anybody who pronounced it the L in Salmon.

Neither do I.

Yeah, it’s ridiculous.

Well, it’s Salmon Rusty.

Anyway.

S-A-L-M-A, it’s Salmon.

Oh, you’re right.

That is Salmon Rusty, yeah.

Okay, so he says, when matter is consumed by the black hole, does it retain its form as protons, neutrons, et cetera, or is it compressed and ripped apart to the more basic elements of the particles, like quarks, et cetera?

I can answer that very quickly.

We don’t know.

Next question.

There you go, let’s move on.

No, no.

So, matter and all the identity it carries as it goes down to the singularity, it’s the singularity where we’re idiots.

That’s unfair.

It’s a singularity where we have profound ignorance.

And Einstein’s theory of relativity, which gives us the black hole in the first place, does not take us to the singularity.

It’s a limit to the theory of relativity.

That’s why we have string theorists who are picking up the slack there.

We do not know what happens to matter at the singularity.

We just don’t.

We do know that the black hole remembers what it ate because Hawking radiation, where particles come into existence from the energy of its gravitational field just outside the event horizon, that gravitational energy through equals MC squared spontaneously becomes a pair of particles.

One side of that particle falls back in, the other side escapes.

If you get the inventory of the particles created out of the gravitational energy field, that inventory of particles exactly equals the history of what the black hole ate.

Remarkably, somehow the imprint of what it ate is remembered in the gravitational field of the black hole itself.

Yes.

That’s pretty wild.

And it’s just wild.

Because you didn’t reach back in and pull it out.

It was, it appeared out of the energy outside the event horizon.

It’s like, oh my gosh.

And of course, Stephen Hawking was at the centerpiece of that.

Yes.

That’s amazing.

Hawking radiation, the evaporation of a black hole.

We actually had them on StarTalk back when we were on the National Geographic channel.

And you might be able to dig it out.

I guess Disney Plus has the entire NetGeo catalog.

They do.

But yeah.

Good stuff, man.

That is good stuff.

All right, here we go.

Colby LaPresi from South Carolina.

And Colby says, once again, with the black holes, if a black hole was smaller than my body, beyond the event horizon in all directions, would it still rip me apart atom by atom?

Yes.

Don’t ever, no, just stay away.

Because what matters is not the size of the black hole, how much mass.

So if Earth were a black hole, it would be the size of a plum.

So if you take all the mass of the Earth, cram it into a plum, and you want to walk by it and believe you’re going to stay intact, that is not going to happen.

It will suck you in and it will funnel you down and you’ll be spaghettified, funneled, and that’s it.

And just kiss your ass goodbye.

Look at that, Colby.

Because you wonder how something your size can fit into something that small.

The very fabric of space-time narrows towards the black hole.

So you will be funneled, basically extruded through the fabric of space and time, like toothpaste in a tube.

That’s crazy, man, when you think about it.

It’s so hard to just like really-

To fatten it.

Yeah, to have a black hole that fits in your palm of your hand and then it sucks you down into a tiny point.

It sucks you, it’s, oh.

I mean, it’s really, it’s oddly terrifying and beautiful at the same time.

Yes, yes, yes.

Wow.

All right, yeah, you’re not getting out of that one.

All right, here we go.

We’re banging them out, banging them out here.

Alan Reyer, Alan Reyer says, can someone address the comet C2022E3?

Hey, Neil, just wanna let you know I’m a big fan and I’m coming to you from the Isle of Malta.

Oh my gosh, cool.

Well, when we come back from our first break, we will address that question on StarTalk.

Hi, I’m Chris Cohen from Hallworth, New Jersey, and I support StarTalk on Patreon.

Please enjoy this episode of StarTalk Radio with your and my favorite personal astrophysicist, Neil deGrasse Tyson.

We’re back, StarTalk Cosmic Query, Grab Bag edition.

Chuck, we left off with someone asking me about comment.

What number did they, what’s the full number?

Our good man Alan Rayer from the island of Malta in the Mediterranean wants to know, hey, what’s the deal with C2022E3?

He gave me the phone number of the comment.

Cool.

Cool.

So that’s been called the great green comment of 2023.

By the way, that ID includes the year it was discovered, 2022, and the semi-month it was discovered.

So there’s that ID is packed with information for someone in the know to know when it was discovered.

And so A, B, this comment based on its orbit, it comes from what’s called the Oort cloud.

This is a spherical shell of comments that surrounds the solar system, but it extends halfway to the nearest stars.

And comments that come from this can come in from any direction at all.

They can loop in from above, from below, and their orbits last tens of thousands of years.

There is no comment that we see from the Oort cloud that was ever seen in the history of civilization.

So you might say to yourself, well, I’d better go out and watch it.

Well, every Oort cloud comment is that.

So it’s possible for something to be rare but uninteresting.

Because they’re comment, right?

Just keep that in mind.

So with this comment, it’s made the news primarily because there’s a chance people could see it.

And right now, like last night, it would be among the days of peak visibility.

I looked up, I didn’t see it.

I’d have to find it with binoculars.

So it’s got a lot of press attention.

By the way, we discover hundreds of comments a year.

So a comment alone is not so…

You know, don’t invest special attention to the existence, to the fact that a comment was discovered.

They’re as common as blades of grass on a lawn.

There’s trillions of them that orbit the sun.

So A, B, the many comments are very faint and you might catch it with binoculars.

And you can see the green in a telescope because it’s a green comment.

Remember, retina has rods and cones and the rods are sensitive to shades of gray.

The cones are sensitive to color, but they require higher intensity light in order to get triggered.

So if you dim the lights in a room, if you look at a room in the dark, but just light leaking in from a streetlight, something through the window, that room is not vibrantly colored.

It’s basically shades of gray.

Because your rods are taking care of business there, just so you can see your way anywhere.

Only when it gets brighter, then you start registering the colors.

So dim comments, no matter what color they are in a telescope, typically you don’t notice that with your eyes, unless you can see them through a big telescope.

They can make the object bright enough to trigger your cones.

So, where to get the green from?

The green, well, we did an explainer on the comet.

I think we did.

Yeah, we did an explainer.

Yes, we did.

So cyanogen is one of the molecules that when it interacts with sunlight, it’s warm, it radiates light.

There are different ways a comet is rendered visible and different chemicals will have different color signatures.

And that’s part of what tells us what comets are made of.

I mean, it’s a beautiful, wonderful thing.

So I love me some comets, but most of them are just not something you’re gonna write home about and say, were you alive in the 20th century?

I promise in your lifetime, we’ll have a really good comet because every 10 or 20 years or so, a really good one comes around.

I wouldn’t count this among them.

Now the real deal is the action is where the asteroids are, my friend.

Don’t worry about the comets.

The action is with the asteroids.

Yeah, but asteroids are dark and they only reflect light.

If they do reflect, they’re dark, so they don’t reflect much light.

So they can come up on you and you wouldn’t know it.

Whereas comets, they say, here I am, look at my tail, look at my beautiful.

Comets are like, yeah, look at me, look at me.

Asteroids are just like, yo, I see a good wallet.

You said that way too glibly.

Give me your wallet.

More likely the asteroid is, yo, give me all your species.

Yeah, they haven’t talked to me about it.

I’m trying to figure out if there’s ever an asteroid big enough that will blow off the entire atmosphere, because anything that hits the atmosphere, the atmosphere becomes like the ocean or anything else.

It would have to be penetrated.

So suppose you had something big enough that it hits the atmosphere, but it’s so powerful that it blows the atmosphere off, but would it then be so big it would destroy the planet?

Next question.

Ah!

No, here’s the thing.

Yo, yo, yo.

That was cold, man.

That was cold.

I know it was cold.

You want to get rid of the atmosphere, you get enough asteroids hitting Earth to heat the atmosphere, and the hotter atmosphere expands and we might lose some outer layers.

Because the molecules start moving faster.

Right.

And some will achieve a scale velocity.

Right.

And so, but a large enough asteroid just punches a hole in the atmosphere.

Real damages, because it doesn’t leave its energy in the atmosphere.

The energy, it’ll barely be slowed down by the atmosphere.

And then it hits Earth’s surface and that’s where it stops moving.

Hey, where did all the kinetic energy go?

It made a crater, it burned the forest.

Right.

It became a shockwave, all that.

Shockwave, so you have to ask, look at the energy budget, where did it go?

That’s where the damage will occur.

Okay, cool, man.

That was cool.

All right, here we go.

This is Nick Davis.

He says, hello, Dr.

Tyson and Lord Nice.

This is Nick from Australia.

I was wanting to know more about how gravity and its influence on time were to influence light on the hypothetical Mylar’s planet and interstellar.

What would happen if someone orbiting outside of the time distortion were to point a super powerful laser pointer at the planet?

Would the beam be dimmer or would the night sky look like?

What would the night sky look like for someone on the ground compared to someone in space?

And let’s take out atmospheres so that we don’t have those distortions.

So here’s what’s interesting to do with your laser the next time you’re trapped in a black hole.

You can try to point your laser out of the black hole and see if anybody gets the signal.

They won’t, all right?

Why not?

Because it’s climbing out of the gravitational well that the black hole is.

And for every little bit it ascends, it’s losing energy.

So the energy profile of your laser will become lower and lower and lower energy until there’s no energy left at all and the light does not escape.

If you were just outside the event horizon and did the same thing, the light would escape, but it would also be shifted in energy.

And it’s called a gravitational redshift.

Look at that.

Gravity redshifts the light.

And so that’s what would happen to the light.

To the, this was only about light or do they also ask about time?

Well, yeah.

So he started off saying, I wanted to know about gravity and its influence on time and light.

And if he remembered from Interstellar, they’re on a planet orbiting a black hole.

And they are severely time dilated.

So that minutes to them are years or years to the folks orbiting far out.

That’s right.

That’s the scene where he comes back and the guy is old, right?

He’s old, correct.

Wow.

Correct.

And it was subtle, but they got it in there.

At the end, the, what was it?

They showed someone in a hospital bed, or was it?

Yeah, I think that was his daughter.

That’s who was older.

Who was older than he is.

Correct, correct.

Because his, so, because his life was prolonged for having been in a very intense gravitational field.

So, yeah, all these are real, and you can calculate it.

And by the way, we do this every day with GPS satellites.

GPS satellites are in a different gravitational field compared with us.

Yes, it’s still Earth, but we are closer to Earth’s center than the GPS satellites are.

So just the way they did in the movie Interstellar, except it doesn’t have to be a black hole to mess with your time, it just will mess with it at a different level, at a lesser amount.

So our time on Earth is ticking more slowly than the time in GPS satellites.

And the GPS satellite is handing us our time.

Well.

So how is it that they match up?

I know how, I know how.

How they do it?

Because the GPS, they’re on CP time.

See, a lot of y’all don’t know about CP time.

Okay, all right, thank you, Chuck.

But see, GPS, y’all don’t know.

They’re down with CP time and they cool with it.

They cool.

And I’m not gonna explain what that is.

If you know what it is.

Google CP time.

If you know what it is, you know what it is.

If you don’t.

Chuck is still in race therapy.

Hey, listen.

That’s amazing.

All right, so the GPS satellites are, no, you’re saying that on Earth we’d be CP time because the GPS satellites being in a different, low gravity field.

Yeah, that’s right.

We’re closer to the gravity, so we are slow.

We’re slow, and the GPS satellite is ahead by a calculatable amount.

Right.

And so when it gives us our time signature, signals, it precorrects it using the equations of Einstein’s general theory of relativity so that we get the proper time on Earth’s surface.

That’s just, I’m telling you, it’s just fantastic.

Yeah, yeah, and people say, well, I don’t believe in science.

It’s like, do you really, do you people, do you know what we do?

Exactly.

We’re living?

Exactly.

Don’t get me started here, Chuck.

You can’t even tell time.

You talking about, you don’t believe in, you can’t even tell time.

I don’t know, what does scientists know?

Yeah, I’ll tell you what they, they put crap in the sky that calculates the time that you can’t even tell.

That’s what science does.

You got the nerve to sit around like, you know, cause seriously, do they really know?

Do they really?

I’m not sure if they really know.

That is, that is just so, I just love that it’s so elegant.

And the fact that it’s, you know, establishing the time, but then relaying the time after it equates what the time will actually be for you.

That’s fricking amazing.

It’s for you because it is touched by Einstein’s general theory of relativity.

Oh, that’s just so good.

All right.

It’s so fricking cool, man.

Like what do people think scientists do?

Right, right.

Exactly.

You think we’re just sitting around.

Oh man.

Here we go.

This is Kyle Marston.

And Kyle says, I know how I perceive the universe.

And I know you and Neil, you perceive the universe as well.

And that our perceptions are pretty similar as biological entities from Earth.

What insights do you have, Neil?

As we now have artificial intelligence, how will they perceive the universe around them?

Like, are they gonna go straight to Dan Simmons’ Technicore or more like Tchaikovsky’s Hive Assembly?

Wow.

Holy crap.

I’m gonna tell you the truth, Kyle.

I’m sorry I read your question.

That’s pretty wild.

Okay, so I have several ways to address that.

One of them is, I don’t know that people thought much about A.I.’s sensory system.

Ooh, very nice.

So can AI feel pain?

I love it.

And can AI taste?

Mm-hmm.

Right.

Right.

And so what we know, we can outfit it with capacity to hear and to see that is vastly greater than our own.

Yeah.

All right.

And self-driving cars.

And those are senses.

These are senses, correct.

So we can outfit AI.

With sense.

I don’t know that we can quite have them taste things.

Why not?

Think about this.

So your olfactory sensors in your brain basically are responding to a molecular stimuli.

Yes.

Yes.

So why wouldn’t we be able to program what that molecular makeup is and then give the computer the same response?

However, yes, we can.

However, we just have centuries of efforts to improve our capacity of sight with microscopes and telescopes and to improve our capacity to hear with sensory devices and microphones.

So we’re much more behind in having machines that can taste.

Okay, I got to.

So we can have a machine that can analyze the chemicals of what’s touching, there’s mass spectrometers that can analyze chemicals.

We can say, if it’s this much that, that tastes salty, this tastes sweet, and this is the umami.

We could teach it that, I guess.

But then it has to sort of bite into you to taste it.

It needs some mechanism to taste.

Right.

Right.

It can’t just be a box on the table.

It’d be the difference between someone telling you what something tastes like and you putting it in your mouth and taste.

Correct.

Right.

Correct.

Right.

All right.

And so, because you can hand them all the ingredients that went into your pie, and then they can analyze those ingredients and they say, hmm, hmm, good, I want some ice cream with that in a pie hour mode.

They might do that, but would they want to?

Right.

Right.

Does AI have our urges?

Does AI have our, you know, typically, it’s only thought of in terms of problem-solving and this sort of thing.

Right.

Not in terms of receiving the sensory pleasures of what it is to be alive.

But let me add to that, that in science, you know, there are people who run around saying, I have a sixth sense, and they want you to be impressed with that.

And I say, well, I’m a scientist and I have a dozen senses.

Wow.

Because I have sensors that can detect all manner of things happening around me that my five biological senses can’t.

I can detect polarization.

I have gravimeters that can detect slight differences in where the mass is beneath our feet.

I can have things, I can have devices that can detect radioactivity that we cannot sensorily do.

I can detect wavelengths of light that fall outside of the visible spectrum.

So I have dozens of senses, you’re not impressing me with your sixth sense.

Wow.

Yeah.

So why don’t you take that little parlor trick back to your seance.

I’m sensing someone who’s passed with the letter J.

No, J is too rare a letter.

You’re right.

Because they never do that.

It’s always D.

Well, I shouldn’t say those in that order.

So that’s cool.

I sense someone here with a relative that has an X in their name.

Those seers don’t…

Isn’t that funny?

That’s so funny.

Yeah.

They never do that.

Well, there you have it, man.

There you go.

So let me ask you this as a follow up to Kyle’s question.

Do you think it’s a good idea to, you know, not as a means of anthropomorphizing machines, but do you think there’s any true benefit in giving them our sense of taste and smell and emotion and so forth?

Whatever it is, I want them to think that humans taste badly.

It’s people.

I don’t want them thinking that we’re a tasty snack.

That will not go over well.

Oh, my God, that’s so great.

That’s very funny.

All right, here we go.

This is Christopher Fowler and he says to serve man.

Christopher Fowler says, hey, Neil, what’s up, Lord Nice?

First, I am just a huge fan of yours, Neil.

Thank you for providing the spark of curiosity to us commoners.

Second, thinking about the Stargate franchise, could there be a discovery in nuclear fusion advancements and understanding, and I use this term very loosely, of the quantum being able to establish an Einstein-Rosen bridge for interplanetary and interstellar travel.

So, let me first agree that we kind of need that if we’re going to go between the planets.

Right.

No, not the planets, between the stars and the galaxy.

Yeah, planets takes a dozen years.

It’s within a human lifetime.

To the nearest stars, it’s tens of thousands of years.

We need a wormhole.

Stargate is basically a wormhole.

They didn’t call it that, but that’s what it was.

Except there was just this metallic ring.

It’s mixed with mysticism and magic and this sort of thing.

So you step into the ring, like Time Tunnel, those who remember this from the late 1960s.

You step into the ring and you’re transported through time.

Do you know where they went in the very first episode of Time Tunnel?

I do not.

They went to the Titanic.

And the guy’s on the deck of a ship, and he says, oh, I’m on a ship, because they got lost in time.

So he’s on a ship.

And I wonder where he’s at.

And he walks by and the camera moves with him, and then the camera moves back, and you see the life, the buoy that says Titanic.

That’s great.

And you say, oh, because you know there was not a second voyage of the Titanic.

So my boy’s going down on this trip.

And apparently they took a poll about if you could move through time, what historical event would you want to witness?

And many people said they wanted to see the sinking of the Titanic.

So it has been hypothesized that that’s why the Titanic sank.

Because when the time machine was finally invented, everyone went back to the Titanic, and there were too many people for the lifeboats.

That’s funny.

Because they were all time travelers and they all died.

And you know what?

If they wanted to go back in time to the Titanic, they deserved to die.

That’s all I’m going to say.

All the places you can go, you’re like, I want to go back to see a bunch of people drowned.

Listen, you know, I don’t care how much you don’t like rich people.

That’s a little too macabre to want to go back to the Titanic.

You got what you deserve.

You’re right on there with them when it goes down.

I hope Leonardo’s Caprio grabs you by the head and pulls you right down with them.

Just like, sorry, Grace.

Okay.

Are you done, Chuck?

I’m sorry.

I don’t know where that came from.

So it’s just about the Stargate, the possible Stargate portal.

We know how to make a…

We know what is required to make a wormhole.

Right.

We just don’t have this material.

So it needs something…

It needs the equivalent of negative gravity.

Right.

Negative energy substance.

And we don’t know what that is or how to make it.

But if we had it, we could make a wormhole.

There you go.

Great question.

All right.

We got to take a break, Chuck.

And when we come back, the third and final segment of StarTalk Cosmic Queries, Grab Bag.

We’re back, StarTalk, Cosmic Queries, Grab Bag.

We left off that last segment, we were talking about Stargate.

Chuck, do you know I have a cameo in Stargate Atlantis?

I did not know that.

I do, I do.

That was the TV show?

Yeah, TV show.

Oh man, I love it.

Please tell me.

And now I gotta, you know I gotta-

I’m an old friend of one of the characters, and I can’t act, so it’s embarrassing, so I shouldn’t have told you.

Oh no, it’s not-

Never mind.

Okay, let me tell you why it’s not embarrassing.

Guess how many appearances I have on Stargate.

So to hell with the haters, see.

That’s what I say to haters.

To hell with you.

Because it’s a cameo, people give you a little more slack.

It doesn’t make a difference, it’s so cool.

I mean, you know, shoot.

Please, I can’t act either, and I’ve been in a bunch of stuff.

And I’m supposed to be an actor.

Hired as such.

I still can’t act.

So, guess what?

You should be very proud.

Don’t ever shoot, please.

The next one.

All right, here we go.

This is Jason O.

Whiter, who says, Greetings, Dr.

Tyson, Lord Nice.

With the expansion of the universe, likely never ending, and space time with it, will individual galaxies be ripped apart by the expansion as objects get further apart from each other?

Will individual bodies be then ripped apart and so forth?

Yes.

Ultimately, as galaxies spread apart, this pressure within the vacuum of space, we call it dark energy.

I don’t know what it is, but it’s there, and it’s doing its thing, and it is most of what is driving the universe right now.

That dark energy will ultimately overcome the gravitational attraction of stars that are held together within galaxies.

It will start ripping apart galaxies.

Then it will rip apart star systems as it pulls planets away from their host stars.

Then it will rip apart solid objects as the molecular bonds that hold the atoms together are broken.

Then it will rip apart atoms where the electrons are ripped from their nuclei.

Then it will rip apart nuclei.

Then it will rip apart the fabric of space and time on the Planck scale.

And at that point, it’s the end.

That is called the Big Rip.

And that will take place in 22 billion years unless something stops it.

Sleep well, Timmy.

Have a nice day.

God, that’s awful.

It starts ripping apart protons themselves.

This is serious stuff.

Look at that.

By the way, when that begins to happen, it happens rapidly.

So it’s a…

You know, once things start getting flying apart, it’s because the more vacuum there is in the universe, the more is this pressure to accelerate it.

So it’s a runaway process.

Okay, got you.

Yeah, right.

It’s like a snowball rolling downhill.

It just keeps going boom, boom, boom, bigger, bigger, bigger, bigger.

The bigger it is, the bigger it gets.

Look at that.

That is insane.

And it’s called The Big Rip.

By the way, in our second StarTalk book, guess what it was titled, Chuck?

No, go ahead.

Cosmic Queries.

In our second StarTalk book, one of the questions is, what is the future of the universe?

And we show all the scenarios that…

And one of them is The Big Rip.

It’s The Big Rip.

If you get that book, you’ll have way more conversation about it than anything I just laid down to this before.

Fantastic.

Cosmic Queries.

Cosmic Queries.

You got it.

All right.

So this is Bruce Ryan.

Hey, what’s up, gents?

Bruce from Virginia here.

I’m wondering what happens to all the heat and energy emitted from stars.

Is it actually heating up the universe?

Or does it just travel until it hits something, then that something absorbs that heat, and then what happens when that heat is absorbed?

I love it.

Okay, so both of those happen.

So what happens is the heat generated from a star goes out in the form of photons of light, and that will travel until it hits something else, and then it gets absorbed.

So you’d think it would just be this tennis match going on back and forth.

However, in the expanding universe, the energy of the photon is diluted into the space that has been expanded for it.

So the energy, the total energy, okay, the total energy is still there, but it’s diluted.

So another, if you have a box of energy, right?

Now I take that energy and spread it into a box twice that size.

It’s the same amount of energy, but the energy intensity is now half in each place.

Now make the box a thousand times as large.

Right.

That energy is all spread out.

The energy intensity is dropped by a factor of a thousand.

Add it all up, you’ll recover all the energy you began with, but the energy density is thinner.

And as the universe expands, the energy density drops, and so the temperature of the universe drops.

Right now we’re three degrees Kelvin, three degrees absolute on the scale, and it’s dropping.

Look at that.

Wow, that’s…

By the way, the James Webb Space Telescope, part of why we put it where it is is that it’s far away from Earth, so Earth, it’s a million miles from Earth, and it only ever points away from the sun.

And it has these baffles that will absorb sunlight that hits it, but reradiate it back to the sun.

A little bit moves through, and we have another baffle that will absorb it and reradiate back to the sun.

And so we have four or five of these layers, and each layer, less and less of the sun’s heat energy makes it through to shield the telescope from any infrared energy that could hit it from the sun.

By shielding away the sun, it drops into equilibrium with deep space.

James Webb Coppertone.

Yeah, I guess you can consider, I guess it is, like sunscreen.

It’s sunscreen.

It’s a cosmic sunscreen.

Thank you, Chuck, for that analogy.

And so by doing so, the sun, which is relatively close to it, all things considered, will not then heat it up.

And so any heat that’s in it will just radiate back out into space.

So this is the thermodynamics of technology and engineering and in the universe itself.

That is cool.

All right.

Man, we’re getting through a lot today.

I can’t believe it.

All right.

Keep it coming.

This is Cameron Bishop.

He says, Hey, Neil.

Hey, Chuck.

I like to think that if I waved at the night sky, someone out there in the distant past is waving back.

Now, in the last century, we have gone from stars might have planets to stars on average have lots of planets.

If you run the numbers, the amount of planets out there is huge.

Given that we exist, it’s not fair to say that with life here on Earth in one hand and the amount of planets in the universe on the other hand, that life is statistically likely in the universe.

And what sort of implications does that have?

Either scientifically or philosophically.

The day we discover life in the universe, it will signal a change in the human condition that we cannot foresee or imagine.

Yes, it is highly likely that life is thriving elsewhere in the universe, not out of wishful thinking, but we’re made of the most common ingredients in the universe.

So whatever life was doing on Earth, it was highly opportunistic.

Life got going almost as fast as it possibly could have.

Within a hundred million years, this sounds like long but it’s short on the time scale of Earth, within a hundred million years we went from organic molecules, which are plentiful in the universe, to self-replicating life.

And the universe is old.

So you combine how long, how much time we’ve had, how quickly Earth managed to create life, how resourceful life is, and to assert that we’re alone in the universe can only be done based on some philosophy that has no foundation in science.

Look at this.

That’s it, man.

That’s it.

That’s it.

And so if you wave, surely someone is waving back.

Somebody’s waving back.

That’s it.

And your wave is not going to get to them for a hundred or a thousand years, traveling at the speed of light.

What I do every time I’m out and I have my laser, I flash it at a star that’s in the night sky, like a pulse, and then I turn it off.

So there’s a length of light.

So if you leave the light on for one second, there’s a beam that’s 186,000 miles long.

Right.

And so that is on its way to that star, and maybe to a planet.

That is so cool.

It’s my space graffiti.

There you go.

I’d say Neil is here.

And so when they show up…

I want to get picked up.

I want to be the only one.

I’m going to say when they show up, and they’re just like, we saw your green signal.

And Neil will be like…

Well, let’s say, what the hell’s been waking us up in the middle of the night?

We saw the signal.

Oh, that was our man, Neil.

Yes.

And by the way, you are now all serving our Godfarm.

What?

Yeah.

Chuck desperately wants to write a screenplay.

That’s clear.

It’d be kind of cool, though, if they land it and they were on their version of what we had as the Crusades.

Except that they do it on an intergalactic basis.

You know?

All right.

Tyler J says, hello, Dr.

Tyson.

Hi, Chuck.

Did they say where they’re from?

Tyler didn’t.

Sometimes they do.

By the way, Cameron, who just asked that last question, was from the UK.

I did not mention that.

Tyler J does not say where he’s from.

Hi, Dr.

Tyson.

What options are there to resolve the crisis in cosmology?

I heard that new data from James Webb Space Telescope has further separated the two values we have for the Hubble constant.

Yeah.

Yeah, this crisis is…

By the way, when I was coming of age, I mean astrophysically, we didn’t know the size of the universe to within a factor of two.

The size or the age of the universe.

To within a factor of two.

Right.

To show you how preside this modern cosmology has become, we are now arguing over a 10% difference between two numbers.

Wow.

And the reason why it’s called a crisis is each of those two numbers is precisely known.

So that the error bars, the uncertainties do not overlap.

Right.

So even though they are close to each other, especially compared to when I was in school, they don’t overlap and so it’s called a crisis in cosmology.

And crisis I think overstates it.

It’s an unsolved problem.

Every unsolved problem is not a crisis.

Exactly.

It’s just an unsolved problem.

And somebody is wrong.

That’s it.

So and there’s the answer.

Somebody is wrong.

And the more you’re measuring two different things and you think it’s the same thing.

Exactly.

Yeah.

You can measure the tail of an elephant to the blind man and the feet and the tusks and the trunk.

And you could tell each other that each the other person is wrong.

But maybe you’re measuring the same thing, but in different parts, in different ways.

And collectively, you all are describing one object and it’s the elephant.

Exactly.

You’re both describing the universe, but maybe you came at it from different sides of the elephant.

Look at that.

I’m not worried about it.

It makes good headlines.

I’m not worried about it.

Yes.

James Webb will help us address this.

That’s fantastic.

That’s wonderful.

By the way, I think in Cosmic Queries, we do talk about the crisis.

Yes.

I think it’s in there.

In the future of the universe.

The crisis of cosmology.

Right.

It’s called a tension.

It’s called a cosmic tension.

Tension between these two different measurements.

So again, in Cosmic Queries, I hate to sound like an ad for the book, but yeah, I mean, it is an ad for the book.

We put a lot of effort into that book.

Yeah.

A crisis in cosmology.

Not to be confused with the crisis in cosmetology.

Which is, how dare you put that eyeshadow with that lip color.

No, no, you know what the crisis in cosmetology is?

I wrote about this in Starry Messenger.

An alien comes to visit, and they see that people with straight hair curl it.

People with curly hair straighten their hair.

People who are short wear heels.

People who, if their body is not, the muscles are big enough, they try to make them bigger.

If there’s something else about their body, they’ll change it.

They do all these things.

And so the aliens will say, you guys must deeply believe that you are irreconcilably ugly.

Given how much money is spent on the beauty industrial complex, they’d be right.

They’d be right.

They’d be right.

If they weren’t right.

If they were to make those assessments, because they’re not even assumptions, they’re just assessments.

You’ve got eyelash thickener, where you don’t like your eyelashes.

You’ve got powder on your cheeks, where you don’t like the color of your cheeks.

You know.

It’s true.

It’s true.

You’ve got paint around your eyelids, and you don’t like the color of your…

What?

So, yeah, they’ll run back home and say there’s no sign of intelligent life on Earth, plus they all think they’re ugly.

You might think I think I’m ugly.

Maybe I just think I’m fabulous.

All right.

I don’t think we have time for anywhere.

Throw one more, and if I have time, I’ll do it.

Let me find something very quick.

I’m going to just…

You don’t know how quick my answer is going to be.

Well, I’m going to make it a quick question.

Okay, good.

Hello, Neil and Chuck from NAU and Flagstaff.

I was wondering if you’ve heard or know about the idea of black hole stars.

I’ve seen videos taking this hypothetical star that has an insane mass, and it could explain black holes in the middle of galaxies.

I asked you this question.

I didn’t realize it.

It’s a weird, a few weeks ago, but any thoughts on that?

Yeah, I don’t know what a black hole star would be other than just a star that became a black hole.

Exactly.

Right, I don’t know.

We have very clear definitions of stars.

What you told me is that we know of nothing that has the mass that would create the black holes that we see at the center of galaxies.

Oh, correct.

Yeah, that’s an unknown, we don’t know what phenomenon is necessary to funnel mass to whatever black hole began there for it to have hundreds of millions of times the mass of the sun.

Right.

And James Webb is going to help us figure that out.

Figure that out.

That’s all, it’s a frontier.

There you go.

And notice I’m not calling it a crisis.

It’s just something we don’t understand yet.

Exactly.

Right.

We don’t get all emotional about it.

It’s just, let’s work on it.

So there you go, pull yourself together, man.

Pull yourself together.

You can get through this.

You can get through this, man.

Pull yourself together.

Chuck, that’s all we got time for.

That’s it.

I love grab bags.

Those are fun.

Yeah, always.

So much fun.

Cosmic Queries grab bag.

Chuck, always good to have you.

Always a pleasure.

Neil deGrasse Tyson here for StarTalk Cosmic Queries.