- I do love talking science with you,
because I don't know Jack about it.
- That means you're still curious,
and you preserved that into adulthood.
- I actually, this is even ready,
but I bought your book last week on Amazon.
I haven't been able to read it yet.
Not because you were coming on.
I actually didn't even know that then.
I just love you.
I think you're so-- - Oh, oh, okay.
(audience applauds)
Okay. - Yes.
His new book is "Letters from an Astrophysicist."
it's so cool.
It's cool.
So, tell me about science.
(laughs)
- Help me.
Help me.
- Okay, so scientists are kids who never grew up.
- Oh, that's what artists are.
- Yeah.
(audience laughs)
Yeah, and what are kids that you're turning,
what's under here and what's this,
and they're taking things apart.
They're basically experimenting, and as parents,
we tend to over constrain their experiments.
You spend the first year of their lives teaching them
to walk and talk, and the rest
of their lives telling them to shut up and sit down.
- [Kelly] Yeah.
- Am I right or wrong?
That's what you do, all right?
- Were you in my house? - Guilty!
(audience laughs) - Yeah, but I need you
to explain a few things,
like sonic boom, go.
- Love me some sonic boom.
- Okay. - Oh.
- I love Sonic. - Okay.
(audience laughs)
- They got a lot of drink options, that's real nice.
- Sonic shakes, yeah, yeah.
So when you sing, when any of us makes any sound,
the sound emanates at the speed of sound from you, okay?
Now, suppose you start moving.
Well, the sound that's in front
of you is not leaving you as fast as the sound behind you,
and there's a point where you move so fast--
(imitates explosion)
Wait, wait, I haven't even gotten to that part yet.
You move so fast
that the sound that you make does not advance
in front of you at all.
- What?
(audience laughs)
- Because you're going the speed of sound itself.
- Oh, so you're
going faster than it. - So when you try
to make a sound, and you go faster than it,
all your sound goes behind you,
and all that sound gathers up on a shock wave,
and that shock wave, if it's an airplane,
is moving through the air,
and by the time it hits the ground, it'll (claps hands) bam!
That's the sonic boom. - What?
Oh, that's what you're saying, okay.
- Because it's faster than the sound that it generated.
- Wow, I wish I'd had a
science teacher like you. - By the way, the sonic booms
in our lives, the crack of a whip, that's a sonic boom.
The tip of the whip.
- The tip of the whip.
- [Neil] Yes, yes, yes.
- [Kelly] That's amazing.
- Is every sentence musical to you?
(audience laughs) - Every time, every time.
- The tip of the whip.
- Black holes.
- I'll try to give you some more of that
by the end of the show.
- I do want to know about black holes.
- Oh, okay, you didn't learn about black holes?
- No, I didn't learn,
'cause I felt like it was wasted on me.
As a kid, you were kind of like, it's over your head,
and now I'm an adult, and I'm into it.
- Number one, avoid them.
(audience laughs) - Avoid them.
Well, who knows what's in them?
Want to go find out?
- Matthew McConaughey did in "Interstellar."
I'm just saying, it works out.
- If you go inside a black hole,
you will not ever come out to tell us what was there.
- But where will you go?
- Well, okay.
(audience laughs)
- Where will we go?
- Okay, all right, so--
- If I didn't have children, I would totally go.
- I will tell you, bring 'em.
(audience laughs)
- No, just in case it's not good.
I'll suffer on my own.
- Here's what happens.
As you get near a black hole,
the difference in gravity between your head
and your feet begins to grow,
which means your feet will fall towards
the black hole faster than your head will.
- Will I get taller?
(audience laughs) - Yes, yes.
- I'm in.
- However, the getting taller part will never cease.
- [Kelly] Wow.
- And so, it'll continue, the whole tidal forces,
and your body will be stretched to the point
where the tidal forces exceed the intermolecular forces
that hold your flesh together,
and so then your body will snap in two,
likely at the base of your waist, at the base of your spine,
then those two parts--
- Like that "Saw" movie.
(audience laughs) - keep falling in
and then those two parts feel the forces,
and they split into two pieces, and then four,
and then eight, and you will bifurcate all the way down
to this cosmic abyss.
- Where does the day bifurcate?
(audience laughs) - Bifurcate, and that's not
even the worst of it. (audience applauds)
- What?
- Okay, that's not even the worst.
- We haven't gotten to the worst part.
- But the worst part is--
- That was the fun part.
- The fabric of space and time narrows.
It funnels down to a point,
so you have a certain width up here, and you get extruded.
- Oh, like my waist.
- To the fabric of space.
Like toothpaste through a tube.
So if you die in that way, we have a word for that.
It's called spaghettification.
(audience laughs)
- Is that a real word?
- Yes, it is a real word.
Look it up.
I composed a poem about black holes.
- Do it.
Yes.
- Just to summarize what you just learned.
- That is terrifying.
- Are you ready?
- Yeah.
- In this feet-first dive to this cosmic abyss,
you will not survive because you will not miss.
The tidal forces of gravity will create quite a calamity
when you're stretched head to toe.
Are you sure you want to go?
Your body's patterns, you'll see them,
will enter one-by-one.
The event horizon will eat 'em, and you won't be having fun.
- No, Neil, it's terrifying.
(audience laughs)
What the hell just happened? (audience applauds)
I have a question I wanted to ask you.
I think you've already answered it.
- What's that?
- What's the scariest thing about the universe?
- Well, it's not falling into a black hole.
- That's not the worst?
(audience laughs)
- No, no, there's way scarier stuff than that.
In five billion years, the Sun will become bloated.
It will expand so large--
- I get that. that it--
(audience laughs)
- I get that.
I expand every month.
- [Neil] I love this show.
Every month it just gets bigger, and then it goes back down.
Okay, go ahead.
- So, how can I continue now?
- 'Cause I'm bloated right now.
This dress is tight.
Okay, okay.
- All right, the Sun, in five billion years,
will bloat to become so large,
it will engulf the entire orbits of Mercury and Venus.
The surface will be so near to Earth
that Earth's temperature will rise exponentially,
and the oceans will come to a rolling boil
as they evaporate into the atmosphere,
then the atmosphere will evaporate into space,
and we will be this charred ember as we get absorbed
by the Sun, descending into the crucible
that is its burning center.
- Holy what?
- Have a nice day. (audience laughs)
- Yeah!
(laughs)
And there's no Segway here,
I just want to kind of gear us away from terrifying.
(audience laughs)
So, when I did your show a couple of years ago,
we talked about the great American eclipse.
- Yeah.
- Which I actually saw at my farm.
- I was so jealous, 'cause I spent all this money
to go to a mountaintop,
and I could have just been invited to your backyard.
(audience laughs) Is my invitation still
in my inbox?
- Oh, my gosh!
- Did I miss the invitation?
- No, honestly, it was a last-minute thing.
We were supposed to--
- Eclipses are not last-minute things!
(audience laughs)
People plan their whole life around eclipses!
- I know, a lot
of people like me. - This ain't a barbecue.
Oops, there's an eclipse!
Was that what happened in your backyard in Tennessee?
- It really was, it was on our farm.
- Y'all need some scientists down there.
- Everybody was like, "Oh, we should go
"to your farm and see the eclipse."
We were like, "Okay," and when we got there,
gone to the gas station, got some glasses,
it was awesome. - Okay, all right.
- And all the animals, everything started making noise.
The crickets, everything started,
and they thought it was nighttime.
- And the craziest behaving animals are the humans.
- We are pretty nuts, but we were drinking too.
(audience laughs)
But wait, I want to leave everyone with a little hope,
okay, 'cause we've gone a little zero dark thirty,
and I'm scared to walk out of my house now,
and I never want to go near a black hole,
so just maybe give us something hopeful.
- Some of the universe derived from a cosmic--
- Something beautiful that makes us smile.
- The atoms of your body are traceable to events
that have long ago occurred in the universe,
especially stars that have manufactured these elements
and exploded, scattering that enrichment across the galaxy,
enabling planets to form, and life upon them,
so when you stand outside and look up at the night sky,
it's not we're here and the stars are there,
we are participant in this great unfolding cosmic journey,
and it is not just figuratively true,
it is literally true that we are stardust.
(Kelly gasps)
- So we're all stars.
(audience laughs)
- It is not that we are in the universe.
That's true, but what's even more true is
that the universe is in us.
(gasps)
(audience applauds)
- I totally want to name my next album
"The Universe Within Me."