Listener Questions 66

Daniel and Jorge answer questions about galaxy collisions, black holes and Nitrogen!

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Episode Transcript

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Speaker 3 (01:24):
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Speaker 1 (01:35):
Go safely.

Speaker 3 (01:35):
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Speaker 4 (01:38):
When you pull up to game night, Ay, all new Camri,
but it's actually Bingo.

Speaker 1 (01:43):
Night Minigolf anyone, It's a Camri five, the all new
all hybrid Camri Toyota. Let's go places. Hey, Orge, are
you preparing your kids for when the end times come?

Speaker 5 (02:06):
Oh?

Speaker 6 (02:06):
You mean when bananas go extinct? Or do you mean
when I retire?

Speaker 1 (02:11):
Yeah? I mean the fall of civilization when we're all
listening to podcast in our caves.

Speaker 6 (02:17):
I feel like I've been preparing my whole life. If
there's a post apocalyptic movie out there, I.

Speaker 1 (02:21):
Probably see it. Well, then I hope you're teaching your
kids some useful skills, you know, blacksmithing, martial arts, cartooning.

Speaker 6 (02:28):
Oh yeah, cartooning for sure, that's going to come in handy.
But you don't think they should learn a particle physics.

Speaker 1 (02:36):
I don't know that anybody's going to be building colliders
out of sticks and rocks.

Speaker 6 (02:40):
Isn't it fire? Doesn't it fire evolve particles colliding?

Speaker 1 (02:43):
A fire is kind of a chemical accelerator. I suppose
there must be some collisions.

Speaker 6 (02:47):
Or are you going to be like, you know, freezing
out there, and you're going to be like, oh no, no, sorry,
the fire is just not fundamental enough for me.

Speaker 1 (02:57):
I think I would be hiding in my cave eating
the last of the world world's chocolate reserves.

Speaker 6 (03:01):
Would that be a useful skill? You could be it
the world's only chocolate tear. Hopefully the zombies like chocolate.

Speaker 1 (03:09):
Dark chocolate is the world's final currency.

Speaker 6 (03:27):
I am Jorge make carctoonist and the author of Oliver's
Great Big Universe.

Speaker 1 (03:30):
Hi, I'm Daniel. I'm a particle physicist and a professor
at uc Irvine, and I purposely got into particle physics
because it was useless.

Speaker 6 (03:39):
You're like, how can I make my time here on
Earth less useful?

Speaker 1 (03:44):
I wasn't so much worried about the positive practical benefits
as the negative. You know, my parents worked in the
weapons programs, and I really really didn't want to do
anything that could be used as the basis of a
death ray.

Speaker 6 (03:55):
I see, but you could have picked something positively useful,
like making a chocolate Yeah, there you go, making people happy.

Speaker 1 (04:05):
Well, you know, my dad did retire from the lab
and then became a blacksmith, so he's definitely got useful
skills for the end times.

Speaker 6 (04:11):
He became a blacksmith. Wow, was he forging like swords
or internal combustion engines in your garage?

Speaker 1 (04:19):
Or what swords? Spears? All kinds of stuff?

Speaker 6 (04:22):
Yes, he's like, I want to eat more weapons.

Speaker 1 (04:28):
I wish I were joking more and.

Speaker 6 (04:30):
More direct, but anyways, Welcome to our podcast, Daniel and
Jorge Explain the Universe, a production of iHeartRadio.

Speaker 1 (04:38):
In which our only weapon is our minds. As we
tackle the quest of understanding the universe, we go forging
through all of the craziness that's out there and try
to weave it all together into an explanation that makes sense.
We hope that whatever the universe is made out of
its tiny little basic bits, that somehow they're danced together
can explain everything that we experience in the universe. We

(05:00):
can somehow find fundamental laws, and then we can also
make sense of it all.

Speaker 6 (05:04):
That's right. We try to hone our knowledge of signs
here and try to prepare you for the end times
when we'll all be looking up at the stars wondering
how do we all get here and how do we
avoid those pesky zombies.

Speaker 1 (05:18):
I guess we should all try to sharpen our minds
so we can slice our way through these problems.

Speaker 6 (05:22):
Yeah, I'm sure having physics knowledge will be helpful only
in the apocalypse, right, you can, I guess, try to
build a laser gun to fight the zombies.

Speaker 1 (05:34):
If the zombies assigned a lot of homework problems, then
I'm definitely there to help.

Speaker 6 (05:38):
Oh, that could be another way to defeat them. You know,
you give them physics problems that are so tricky that
their brains explode, and that everyone knows that's how you
kill zombies.

Speaker 1 (05:47):
Wow, Yes, exactly too many into girls.

Speaker 6 (05:55):
Coculus.

Speaker 1 (05:55):
No, you know, Newton definitely believed in zombies. Really, Newton
definitely believed in some weird stuff. I don't know about zombies,
but you know, he was an alchemist and he definitely
was a fan of the arcane.

Speaker 6 (06:11):
Wasn't he really into currencies too.

Speaker 1 (06:13):
Mm hmmm, yeah, exactly.

Speaker 6 (06:15):
At some point became like a coin master or something.

Speaker 1 (06:17):
He was definitely a weird dude.

Speaker 6 (06:19):
Yes, by word, do you mean a genius who basically
invented science?

Speaker 1 (06:26):
I think that's actually giving him a little bit too
much credit. But yeah, he invented lots of physics and
big chunks of math, and I think he would be
pretty tickled if we could use calculus against the zombies.

Speaker 6 (06:37):
Oh well, I'm sure a lot of people will be
relieved to learn it's useful for something after all that
work in high school.

Speaker 1 (06:43):
Yeah, they can integrate it into their lives.

Speaker 6 (06:46):
Oh boy, that was very ridico. But anyways, we do
like to think about the universe and we try to
explain it here on the podcast, and sometimes that involves
answering questions.

Speaker 1 (06:56):
That's right, it's not just Isaac Newton who's thinking about
the nature of the universe. It's everybody. The goal of
science is to understand the universe, and that means for
everybody to figure it out, and that, of course means
everybody's got to be out there thinking about the universe,
asking questions, wondering how it all works, and we want
you to be doing that. We hope that this podcast
stimulates your curiosity. You hear on the podcast about the

(07:19):
questions we are asking, but we want to hear about
the questions you are asking, and then we want to
answer them. So if you have questions about the nature
of the universe or something you heard about on the
podcast or something you heard about on gas another podcast,
please write to me to questions at Danielanjorge dot com.
We'll clear it up for you.

Speaker 6 (07:36):
Yeah, because it's part of human nature to be asking questions,
and it's totally fun to ask questions as well, and
so here in the podcast we sometimes like to answer
questions that listeners send us, and so to be on
the podcast, we'll be tackling listener questions number sixty six.

Speaker 1 (07:56):
You have a sixty six related snide.

Speaker 6 (07:58):
Comment warning, Daniel. If we keep going, we're gonna hit
listener questions six sixty six.

Speaker 1 (08:05):
Oh, I thought you were going to warn you about
listener question sixty nine, where we turned everything upside down.

Speaker 6 (08:11):
I have warned you repeatedly about that milestone, and you
don't seem very concerned.

Speaker 1 (08:18):
I'm mindlessly barreling towards it.

Speaker 6 (08:21):
We'll just maybe we'll record it, but then we'll censor it.

Speaker 1 (08:25):
Maybe we'll just skip it. We'll go straight to seventy.

Speaker 6 (08:28):
Yeah, seventy isn't sixty nine.

Speaker 1 (08:30):
Nobody says that. Don't make that a thing.

Speaker 6 (08:35):
I don't care if other people say, oh, I see,
but yeah. We do like to answer questions here on
the podcast that listeners said this, and so today we
have three awesome questions. They are about galaxies colliding but
extreme forces, and about the air we breathe. So let's
jump right in. Our first question comes from Pedra, who
hails from Boston.

Speaker 1 (08:55):
Hi, Daniel, and Jor.

Speaker 7 (08:57):
I'm routinely here not to worry about the impending collision
between our galaxy and the Andromeda galaxy, since the space
between the stars within each galaxy is so great there
won't be any direct collisions. However, on some of the
podcast episodes, it seems as though the orbital stability of
the planets in our solar system isn't all that great?

(09:18):
For example, some planets may have traded places, while other
planets could have been captured or ejected. So really, which
argument wins? Do I need to tell my descendants to
start worrying about it? In four point five billion years,
I really want them to see the Sun become a
red giant. Thanks for the great podcast.

Speaker 6 (09:37):
All right, interesting question. Basically, should we be worried four
and a half billion years from now?

Speaker 1 (09:43):
Yeah? Exactly if we're all alive? Or should the zombies
that have succeeded us, should they be worried about.

Speaker 6 (09:51):
What's going to happen? I think that's the best part
of being a zombies. You don't have to worry about anything.

Speaker 1 (09:57):
As long as you've killed off all the people who
might assign you homework problems, you're.

Speaker 6 (10:00):
Fine, man. I think the best part of being a
zombie is you can just turn your brain off.

Speaker 1 (10:04):
Don't you need to protect it from exploding?

Speaker 5 (10:06):
Right?

Speaker 1 (10:06):
Isn't that the kryptonite of zombies?

Speaker 6 (10:08):
Well? I think fire also kills zombies.

Speaker 1 (10:10):
Oh boy, wow, yeah, I'm so glad you've been doing
this research.

Speaker 6 (10:13):
I'm glad the people I'll be hanging out with know
how to make a fire.

Speaker 1 (10:19):
But I think Petra's question is really touching on two
things we hear about a lot in science, One that
our galaxy is colliding with another galaxy, and the other
that our solar system is kind of fragile, that the
orbits are not really that stable, and so he's worried
that even if stars are pretty dilute in the galaxy,
would our solar system get upset?

Speaker 6 (10:41):
Basically, what's going to happen when our galaxy collides with Andromeda?

Speaker 4 (10:45):
Like?

Speaker 6 (10:45):
Be safe? Like, is nothing going to happen to us?
Or should we be concerned that maybe our plant might
get disrupted and thrown out into space.

Speaker 1 (10:53):
Yeah, it's definitely a valid concern, and it touches on
a lot of really interesting physics. And first thing I
want to talk about is why Andrama is going to
collide with the Milky Way, because I get a lot
of questions about exactly this. People hear us talking about
how the universe is expanding and space is being created
between galaxies, and then they hear us talking about how
Andromeda is coming towards us and say, how does that

(11:15):
make any sense? Why isn't space expanding between us and
Andromeda and pushing it further and further away. And so
first we should try to reconcile that apparent contradiction.

Speaker 6 (11:25):
Mm. Yeah, because we talked about like, how because dark
energy is expanding the universe, the galaxies out there getting
further and further away from us. But we've also talked
about how Drama is in a collision course with our galaxy.

Speaker 1 (11:38):
Yeah, And the answer comes down to distances, and dark
energy is something that gets more powerful for distant objects.
It's basically like a chunk of space grows a little bit,
and so more chunks of space are growing more. So
a little tiny chunk of space is hardly growing, but
a vast distance between our galaxy cluster and a really
distant other galaxy cluster that's kind of growing a lot.

(12:02):
And gravity is the opposite. Gravity gets weaker with distance.
As things get further apart, gravity fades away. So for
stuff that's really close together, like the Earth and the Sun,
or even our galaxy in the neighboring galaxy, gravity wins
over dark energy. Things that are really really far apart,
like clusters of galaxies, not individual galaxies, dark energy is winning.

(12:23):
And most of the universe is far apart from most
of the universe, so mostly things are expanding away from
each other, but in little neighborhoods, like our cluster of galaxy,
stuff is still getting pulled together by gravity. So gravity
is the reason the Milky Way and Andromeda will collide
in a few billion years?

Speaker 6 (12:39):
Is it gravity? Or is it just that we just
happen to be in a course that intercepts the course
of Andromeda, Like, is Indrameda really being attracted to our galaxy?
I mean, obviously it is, but is it really significant
to call it the main reason it's we're going to
collide with it?

Speaker 1 (12:54):
It definitely is. I mean, the Milky Way Andromeda are
part of a cluster of galaxies, and that cluster exhibits
because of gravity, so it's holding it together, and the
galaxies are sort of sloshing around. It's not guaranteed at
any moment that they're going to hit each other, but
it's gravity that holds them together, that's pulling them together.
It's sort of like asking if a comet falls towards
the Sun and it collides to the Sun, why is

(13:16):
that Well, it's definitely because of the gravity. That doesn't
mean that every comet does collide with the Sun. Gravity
is not omnipotent. Sometimes comets go around the back of
the Sun in the same way in the local cluster.
Not every galaxy is gonna collide with every other galaxy
as soon as possible. Sometimes they pass around each other.
But it is gravity that's pulling these two together.

Speaker 6 (13:35):
Well, I guess what I mean is like if you
have to asteroids, for example, in the Solar System, and
they're gonna collide with each other. I mean, sure, they're
in the Solar System together because of the gravity well
of the Sun, but the fact that they're colliding with
each other as opposed to not colliding, it's mostly just
kind of look right, Yeah.

Speaker 1 (13:51):
It's gravity plus chance. It's possible to have a cluster
where galaxies like ours and Andromeda don't collide until later on.
Eventually everything is going to collide and it's all going
to collapse into one super massive black hole. So it's
really just a waiting game.

Speaker 6 (14:05):
But the collision that's going to happen in four and
a half billion years, that's basically luck, right, It's not
like it's inevitable, like if our galaxy was moving a
few degrees in another direction, or to the right or
to the left, we wouldn't be colliding with Andromeda, would we.

Speaker 1 (14:19):
Yeah, that's right. If you changed the initial conditions, that
collision might happen later. It also might happen earlier. Right,
It could be that we're lucky we got this far
now colliding with Andromeda. So yeah, the whole system is
very chaotic, but it is gravity. But gravity is really
the only force at play here.

Speaker 6 (14:33):
M and So the reason we're worried about Andromeda and
not other galaxies is because the other galaxies are further away,
and those are definitely moving away from us because of
dark energy, or are some of them potentially getting closer
to us.

Speaker 1 (14:46):
Everything in our galaxy cluster is gravitationally bound, which means
it has enough gravity to hold itself together and resist
the pull of dark energy. Galaxy clusters are like the
biggest thing that have that property. Anything that's larger than that,
what we call a supercluster, is probably too big and
too spread out for gravity to hold itself together, and
dark energy is going to win. So that's sort of

(15:08):
the tipping point. So anything that's in our galaxy cluster
is eventually going to collapse. Into one big super massive
black hole, and we're talking very very far in the.

Speaker 6 (15:16):
Future unless dark energy changes, right, Yes, like if it accelerates,
then it's going to get a little more crowded, but
it or if it like weekends, things might get a
little room hear.

Speaker 1 (15:27):
Yeah, I think it's the opposite. If dark energy accelerates,
then even our galaxy cluster is going to get torn
apart because it becomes more powerful than gravity. We talked
about that once on the podcast. There's even a theory
of like phantom dark energy, where dark energy gets so
powerful that it tears apart atoms and even protons. And
if dark energy weakens, then gravity wins over larger distances

(15:47):
and it might gather together even superclusters.

Speaker 6 (15:50):
Right, that's what I meant. I meant the opposite of
what I said.

Speaker 1 (15:52):
But you're definitely right on the conceptual part, which is
that we don't know what dark energy is or what
it's going to do, and we can't really predict it.
So this is assuming a naive extrapolation of dark energy,
which is basically all we can do at this point.

Speaker 6 (16:04):
All Right, so we're in a collision course with Andromeda.
What's going to happen when we collide.

Speaker 1 (16:09):
So when we collide with Andromeda, there's a bunch of
different components of the galaxy, and you really need to
think about each of them individually because they all have
different behavior. So, for example, the gas and the dust
that are in the two galaxies, those are going to
collide and you're going to get all sorts of dramatic stuff.
It's going to see the creation of lots of new stars,
which would be really exciting. But the stars themselves are

(16:30):
very different from the gas and the dust. Right, the
gas in the dust is very spread out. It's definitely
going to smash into the other stuff. But stars are
very different from gas and dust. They're not as spread out.
They're tiny, and they're clumpy, and they're really really dilute.
So when stars approach other stars, it's very hard for
them to actually collide because space is really really big
and the stars are really really far apart.

Speaker 6 (16:52):
I guess how far apart are they? Like how far
is there are year's neighbor?

Speaker 1 (16:55):
So our nearest neighbor is light years away, right, the
closest star to us almost four light years away, and
the Sun is the tiny fraction of a light year wide.
I mean, if you shrink, for example, the Sun down
to the size of a tennis ball that you could
hold in your hand, then the nearest neighbor star would
be four or five thousand miles away.

Speaker 6 (17:14):
WHOA, that's like on the other side of the Atlantic kind.

Speaker 1 (17:18):
Of yeah, exactly. So imagine you're throwing a tennis ball
and somebody on the other side of the ocean is
throwing a tennis ball. What are the chances that they're
going to hit each other over the ocean? Like basically zero?

Speaker 6 (17:31):
But I guess how wide is the sphere of influence
of something like the Sun, Like how close do you
need to get to it before you feel it's gravity?

Speaker 1 (17:40):
Yeah? Exactly, good point, because we're not actually just interested
in like a collision where like the two stars really
touch each other and merge and become one. Stars can
pull in each other if they're even near each other, right,
And that's really what Petra's question is about, is how
close does the star need to get to distort our
star or distort the orbit of stuff around the star?
Are right? Because near misses can destabilize things, and we

(18:04):
know that already in our galaxy because other stars are
moving relative to the Sun. Sometimes they come closer, sometimes
they come further away, and that can distort the orbits
of stuff in our Solar system. So it's not a clear,
crisp answer. It's not like there's a certain distance within
which something happens and out of which nothing happens. It's gradual, right.
The closer it comes, the greater the gravitational distortion.

Speaker 6 (18:26):
But I guess maybe it depends on how unstable our
orbit is or how fragile our orbit is. Do you
have a sense of how precarious are a path around
the Sun is? Like if I bring in another Sun,
I don't know, a few million miles away, is it
going to affect us and kick us out of the

(18:47):
Solar System or maybe cause us to fall into the Sun,
or are we going to be okay?

Speaker 1 (18:51):
Yeah, it's a good question. The Earth is pretty stable,
like just the Earth in the Solar System is a
pretty stable orbit. There's a lot of stuff going on
that's going to end fluence the Earth's orbit that makes
its orbit change. For example, like the Sun is losing mass,
so it's gravity shrinks. The Sun is also pushing on
the Earth, not just pulling on it with gravity but
its wind pushes on the Earth. There's effects of Jupiter,

(19:14):
there's gravitational radiation. But you're right, the biggest wild card
are like things from outside the Solar system. And this
is something we've thought about, not just in the case
of another galaxy, but again just stuff in our Solar system. So,
for example, there is a star it's called Glease seven
to ten that we've been tracking, and we predict that
it's gonna come kind of close to our star. It's

(19:37):
gonna come within one twenty fifth of the distance to
Proxima Centauri. So Proximus Centauri is four light years away,
and so this is gonna come like an eighth of
a light year away from our star.

Speaker 6 (19:50):
Oh wait, wait, wait, so this is a star that's
gonna come within one twenty fifth of the nearest star. Yeah,
would it becomes the nearest star if it's coming close
to us?

Speaker 1 (19:57):
Yeah, that's just for scale. Our current near stars four
light years away, this one's going to come within one
twenty fifth of that distance. Again in the far far future.

Speaker 6 (20:07):
How far in the future, in about one and a
half million years. Oh that's pretty soon cosmically speaking.

Speaker 1 (20:14):
Yeah, it's a lot of generations to survive between now
and then. But yeah, that's not far away, and it's
definitely a lot sooner than when the Milky Way collides
with Andromeda.

Speaker 6 (20:24):
And this is a star that's like traveling through space
relative to us, or are we traveling close to it?
You know what I mean? Like, is this an anomaly
or in our quiet neighborhood or is it all part
of the movement of the stars.

Speaker 1 (20:37):
It's part of all the movement of the stars around
the center of the galaxy. You know, all the stars
are orbiting the center, and they orbit at different velocities. Also,
the stars are moving up and down. They're sort of
like wiggling through the plane of the galaxy. And so
the stars that are in our immediate neighborhood change over
millions of years as these stars sort of swim through
the Lazy River differently. So this is a totally normal

(21:00):
thing to happen.

Speaker 6 (21:01):
And what do scientists predict this is going to happen
when the start flies close to us? Is it gonna
disrupt us or are we going to feel it?

Speaker 1 (21:09):
So we are probably not going to feel it directly,
in the sense that it's not going to come close
enough to perturb the Earth's orbit. So that's already kind
of an answer, Like you can come fairly close to
the Solar System, you know, within an ace of a
light year and really have no effect on the Earth's
orbit directly, but it could have serious impacts for life
on Earth because it could impact stuff that's in the

(21:30):
outer Solar System that could then rain down on the
Inner Solar System. The very far edges of the Solar System,
past Pluto and all the dwarf planets is a theoretical
cloud of trillions of icy objects called the Ort Cloud,
and we think it's probably the source of long period comets.
These things are really really far away compared to stuff
in the Inner Solar System or even to Pluto, and

(21:52):
so a nearby passing star could disturb some of these.
There's lots of them, and they take just like a
little nudge to fall out of their orbit come barreling
into the inner Solar System, where they could become very
high speed, very dangerous comets that could impact on the Earth.

Speaker 6 (22:07):
WHOA, but it maybe it might get lucky not get
hit by, right, because even the space between us and
the Sun is huge.

Speaker 1 (22:15):
Yeah, absolutely, we might get lucky, and we could get
protected by Jupiter. Right, Jupiter has a lot of gravity
and it tends to shield the inner Solar System by
pulling these things towards it. Like when comet Shoemaker Levey
came through the Solar System in the nineties, it impacted
on Jupiter and that wasn't an accident. Not only is
Jupiter just a much bigger target, but it has that gravity.
But it's not a die you want to roll. It's

(22:35):
sort of like playing cosmic Russian Roulette. You know, if
a star comes by and dislodges a lot of oork
cloud objects tens millions even for example, then we're gonna
have to get lucky a lot of times to avoid
being hit. So that's the most likely scenario for Glease,
and also for the collision between Andromeda and the Milky Way,
that our ort cloud gets perturbed.

Speaker 6 (22:55):
Well well, but I guess what is the scenario that's
going to happen when we coll but Andrameda. Are we
going to see a lot of these stars flying as
close as Glee or is it going to be worse
because I imagine, you know, the nearest star to class
is pretty far away, but you know, we're colliding with
a cloud of one hundred billion stars. Maybe that increases
the chances of something flying closer.

Speaker 1 (23:16):
Yeah. Actually, Andromeda is much bigger than the Milky Way.
There's lots more stars in Andromeda than in the Milky Way.
It's really a big, fat galaxy. I mean in a
very positive way. And so there's no specific answers. There's
just chances, right. The chances of a direct collision are zero,
the chances of a near miss are larger. The chances
of stars flying sort of within a light year or

(23:37):
so is reasonable. I haven't done the actual calculations, don't
have numbers, but qualitatively it's extraordinarily unlikely for a direct
star star collision. I think it's quite likely for a
near miss like Glease seven to ten. But I think
the most likely scenario is that no star comes really
anywhere near us. Even though there are a lot of them,
there are also very very spread out.

Speaker 6 (23:57):
No, should we just think you're word for it, or
should maybe one of you guys get on the computer
and simulate this to figure it out.

Speaker 1 (24:05):
We've got four and a half billion years to figure
it out. So yeah, that's enough computation time.

Speaker 6 (24:09):
I don't know. I like to plan ahead as you know. No,
you gotta get ready.

Speaker 1 (24:14):
The problem with these calculations is that the further in
the future you have to extrapolate, the more uncertainty there is.
Right Like, NASA can predict the path of these objects
for one hundred years very precisely. You ask them to
tell you where they're going to be in five billion years.
They have no idea because small uncertainties add up over
time to make those predictions essentially useless. So our understanding,

(24:36):
for example, of the dark matter in the Milky Way
will affect this, and the dark matter and Andrama and
the dark matter between us and them. So we could
do a calculation and give you a number, but it's
gonna be different next year, and it's gonna be different
in a million years, it's gonna be different in a
billion years.

Speaker 6 (24:49):
Well, I mean, you don't need to predict what's going
to happen exactly, but could you maybe get a statistical sense,
Like if I take a cloud of stars like the
Andromeda galaxy, and you take a cloud of stars like
the the Milky Way galaxy, and you smash them into
each other at the speed are going what are the
chances or how likely or you know, how often would
star come near as enough to disrupt our orbit.

Speaker 1 (25:10):
That's totally possible, and probably somebody is working on that,
but I haven't actually seen that number anywhere.

Speaker 6 (25:16):
All right, Well, then the answer for Petra is hopefully
not nothing bad will happen. Daniel doesn't think.

Speaker 1 (25:23):
Don't worry too much about Petra. Zombies are much more likely.

Speaker 6 (25:26):
Yeah, don't collide with any zombies if you can't, especially
when it's with teeth.

Speaker 1 (25:31):
But keep working on those intervals. That's going to save
you in the end times.

Speaker 6 (25:34):
That's right. Bring your math book whenever you go out
foraging for you know, particle colliders to start your fire.

Speaker 1 (25:42):
Or do what my dad did. Become a blacksmith and
make your own weapons.

Speaker 6 (25:46):
Oh yeah, that's a good suggestion. Or just go to
Daniel's garage and you know, steal some of those swords.

Speaker 1 (25:54):
I wouldn't recommend that. That's pretty well protected.

Speaker 6 (25:58):
By math. If you come within ten meters, you'll be
faced with some physics questions, or you could just blast
the podcast out in speakers. They'll keep every one away.

Speaker 5 (26:09):
All right.

Speaker 6 (26:10):
Let's get to our other questions here today, and we
have some questions about extreme forces in the universe, and
about what kind of air are we all breathing? So
we'll dig into those, but first let's take a quick break.

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Speaker 1 (29:40):
When you pop a piece of cheese into your mouth
or enjoy a rich spoonful of Greek yogurt, you're probably
not thinking about the environmental impact of each and every bite,
but the people in the dairy industry are. US Dairy
has set themselves some ambitious sustainability goals, including being greenhouse
gas neutral by twenty to fifty. That's why they're working
hard at every day to find new ways to reduce waste,

(30:02):
conserve natural resources, and drive down greenhouse gas emissions. Take water,
for example, most dairy farms reuse water up to four
times the same water cools the milk, cleans equipment, washes
the barn, and irrigates the crops. How is US dairy
tackling greenhouse gases? Many farms use anaerobic digestors that turn
the methane from maneuver into renewable energy that can power farms, towns,

(30:23):
and electric cars. So the next time you grab a
slice of pizza or lick an ice cream cone, know
that dairy farmers and processors around the country are using
the latest practices and innovations to provide the nutrient dense
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Speaker 6 (30:48):
All right, we're answering listener questions, and our second question
comes from Dirk, who comes from the planet Earth.

Speaker 1 (30:56):
I guess probably we hope so, no, we hope not.

Speaker 6 (31:00):
Yeah, Hi Daniel and Jorge.

Speaker 5 (31:04):
So I have a question about extreme forces. I know
gravity is one of the weakest forces in nature, but
it seems like there's no limit to how much gravity
there can be, and once you have enough of it,
an event horizon is formed and a black hole is made.
Even then more maths can be added and gravity will
continue to increase. Can this be done with any of
the other forces? Like can a magnetic field become so

(31:26):
strong that it forms its own kind of event horizon?
Or is there a limit that prevents the other forces
from increasing infinitely? Thank you?

Speaker 6 (31:34):
All right, interesting question. I guess the question is how
extreme can other forces get? Can you make like a
magnetic black hole or a weak black hole.

Speaker 1 (31:44):
Yeah, super fun question, really great to think about, and
I love the sort of philosophy behind this question. Trying
to make connections between forces and trying to understand the
differences between ideas. This is really how you make progress
in physics. How you build to consist model in your head,
try to understand where that model doesn't work and where
the pits don't fit together, and then try to understand

(32:06):
how they can possibly click together. So kudos to you,
Derek for thinking about it this way and for asking
this great question.

Speaker 6 (32:13):
All Right, the question is Derek is wondering, like, we
know that a black hole happens when you gravity gets
so intense that it becomes basically a black hole with
an event horizon. Can that sort of thing happen with
the other forces in nature, like electromagnetism or the weak
force or the strong force. Can you get a situation
where the magnetic force is so strong it can maybe

(32:35):
creates its own kind of event horizon.

Speaker 1 (32:37):
Yeah, So super fun question, and it's tempting to think
that there is because Derek probably thinks about gravity as
a force in the same way he thinks about magnetism
as a force, and that it creates an acceleration on objects. Right,
Two objects, as Newton described that have mass will pull
on each other the same way two objects with electric charge.
The electric force will pull on them or push on them,

(33:00):
and the strong force pulls and pushes on things that
have color charge. And so it's tempting to think about that.
It's very intuitive, but remember that gravity is not actually
a force. It's Our understanding of gravity today is that
it represents the curvature of space time itself, and in
many ways that's equivalent. Like most of the time, you
can think about the curvature of space time and from

(33:21):
that you can get exactly the same behavior that Newton
would have predicted, but it's also crucially different in many respects.
There's lots of things that the curvature of space time
can do that the simple force of gravity cannot do.
And form an event horizon is one of those things.
So Einstein's reconception of gravity as a curvature of space

(33:42):
time describes all of Newton's physics, but also more than that,
it doesn't just reformulate gravity as another way to think
about it, it adds new capacity to gravity. New things
that it can do. And so the force description of
gravity cannot create an event horizon, but the curvature description
of gravity can create event horizons. And so the other forces,

(34:04):
which can't be described in terms of curvature, can't create
event horizons. That's not something a force can do. Only
spacetime curvature can do that.

Speaker 6 (34:12):
Well, I guess I might ask, are you sure about that?
Couldn't you define the event horizon as the point at
which the force of gravity is so strong that nothing
can escape it.

Speaker 1 (34:23):
I'm definitely not sure about that, because we don't understand
gravity right. Gravity is really weird. Einstein's theory is beautiful,
but we also know that it's flawed. We don't understand
how singularities could form. We don't understand why gravity seems
to not be quantum mechanical, or if it is when
you zoom in enough, for example. So everything we say
here today assumes that GR is correct, but we know

(34:46):
that GR is not correct ultimately, and so there's lots
of things to be learned, and in the far future
this could all be totally wrong. So yeah, absolutely not,
But you're right. First, we should define what we mean
by an event horizon, right, and a black hole can exist.
The reason we have event horizons, the reason that curvature
can do this and the forces cannot, is that curvature

(35:07):
does something to space. It changes the shape of space,
like the relationship between points. So you can think about
it as like a region from which even a photon
cannot escape, right, And that again is something gravity can do.
But you can't do that with magnetism or electric force
or the strong force.

Speaker 6 (35:24):
Well, I guess what I mean is, like you know,
for example, you might say that the Earth has an
event horizon, right, Like there's a point and a velocity
at which you can escape to Earth, and there's a
point at which you cannot escape Earth, right, So maybe
you might be able to call that the event horizon
of the Earth gravity, black holes, event horizon. It's just that.

(35:44):
But taking to the extreme where you're talking about not
even light being able to escape, I wonder if you
can do that the same with a magnetic field or
like a magnetic force, Like, is there a point at
which not even like a super fast moving charged particle
will escape the attractive force that something has Electromygnetically, I.

Speaker 1 (36:01):
Mean, you can definitely form bound states right, Like the
Moon is bound to the Earth gravitationally, but it can
still escape, right, Or photons from the Moon can definitely
escape the gravitational system. And that's not just like a
difference in degree, it's a difference in kind. Right. The
inside of an event horizon really is cut off from

(36:21):
the rest of the universe. Nothing that happens there can
influence anything that happens outside the universe, whereas things that
happen on Earth can always influence things far away. It
just takes some time. So it's a question of like causality,
like are these things linked or not? Can one area
of space affect another? You can definitely attract things together,
and they can even be stuck together, and they can

(36:42):
be stable, and they can even last for millions or
billions of years or configurations like the proton might last forever,
but you know, the quarks inside the proton could still
potentially escape you give them enough energy. It's a bound state.
That's not the same thing as an event horizon.

Speaker 6 (36:57):
But could you say that, like a charged ball ofity
has an escape velocity to it and a point at
which no charge particle can escape it.

Speaker 1 (37:05):
A charge ball, for example, definitely has an escape velocity,
like there's a minimum energy you would need to escape
the potential well created by that ball, and things below
that energy are bound to it. But there is still
always an escape velocity. And that's why photons are a
useful way to think about event horizons because there's no
force that can bound a photon. Like, photons always move
at the speed of light locally, and there's no force

(37:27):
that can prevent them from doing that. But changing the
direction of space, right, changing the configuration of space the
way gravity does that can trap a photon because it
can change space from flat to curve. It can make
the photon move in a circle forever, which is sort
of amazing. And so that's why gravity can do this,
which no other force can do.

Speaker 6 (37:46):
But I guess light is an electrically neutral right, Yeah,
So I wonder if you can envision, like, is there
a ball of charge. They can be so intense that
not even a core going at the speed of light
can escape it. You maybe call that the event horizon
of an electromagnetic force.

Speaker 1 (38:04):
So you take a ball of charge has a very
strong electric force, right, and now imagine some electron near it,
and you're wondering, like is it possible to have that
ball be so electrically charged that even an electron moving
at the speed of light couldn't escape it. Yeah, yeah,
it's a great question. The problem is that electrons can't
move at the speed of light because they have mass.

Speaker 6 (38:24):
Right, Well, of course I know this, but like, if
it was moving at the speed of light, is there
a point we're closing on nine point nine nine nine
percent of yeah, the speed of light. Is there an
event horizon for that ball of positive charge?

Speaker 1 (38:36):
Right? And I bring up the velocity not just to
be like actually, but because velocity is the wrong way
to think about it, because for a massive object, energy
is the right way to think about it. As you say,
you can't get to the speed of light, you can
get arbitrarily close, but there's no limit to the amount
of energy that an electron can have, and so you
can just keep putting energy into that electron and eventually
it will escape that ball of charge. So no, there's

(38:59):
no way you can try crap an electron forever. You
can't create an event horizon using electric charge. You could
always just give that electron more energy and it would
escape your ball of charge, no matter how big it.

Speaker 6 (39:09):
Is all right, So then the answer for Derek is no,
you can't make an electromagnetic black hole.

Speaker 1 (39:15):
Yeah, And I think there's another wrinkle there, which is
something you brought up, which is photons are neutral electromagnetically, right,
And I think that's really cool and kind of weird
that photons, even though they carry electromagnetic information, they don't
feel the force themselves. And that's something true about all
of the forces, electromagnetism, the weak force, a strong force,
there are always some particles that are neutral to it, right,

(39:37):
So like the strong force can create really really strong
bound states, but then neutrinos ignore it, right, they would
just fly right through it. So in that sense, an
event horizon for like electromagnetism wouldn't really be an event
horizon even if you could make one, because some particles
ignore it. The amazing, awesome thing about gravity is that
nothing can ignore it. Gravity is just linked to energy.

(39:57):
So anything that has energy, we just basically anything in
the way we conceive of it is affected by gravity.
It's inescapable.

Speaker 6 (40:05):
Oh all right, Hm, I'm still wondering, like could you
make that calculation? Like what did you take an electron
give it this speed of light. Could you use that
to compute a positive ball of charge strong enough for
which that's the escape velocity.

Speaker 1 (40:21):
Well, if you have an electron and you effectively give
it velocity the speed of light, you're giving it infinite energy,
and of course that's impossible. But what that means is
that there is no ball of charge that's powerful enough
to bound it because there's infinite energy, so has more
energy than any energy level in that bound state unless
you make that ball infinite. Right, So now it's just

(40:42):
like infinity versus infinity.

Speaker 6 (40:44):
Well, I guess what I mean is like, when you
compute the scape velocity of something escaping Earth, you're not
actually using the relativistic equations, right, You're just kind of
using more basic math. You're ignoring relativist effects.

Speaker 1 (40:56):
Right, Yeah, the simplest calculations ignore relativistic effects. But I
don't think relativistic effects are really relevant for the Earth.

Speaker 6 (41:03):
Right. But so let's say I do that for an
electron and I give it the speed of light. Could
I compute an event horizon, even though maybe it's not realistic,
but it is there one.

Speaker 1 (41:15):
So you're saying, if I ignore the fact that electrons
can't go the speed of light and I ignore relativity.
Can we make an event horizon for an electron?

Speaker 6 (41:23):
Yeah, just like when we compute the scape velocity of
a satellite or a spacecraft, we sort of ignore that too.

Speaker 1 (41:28):
You can definitely calculate and escape velocity right or effectively
an energy beyond which the electron is free and below
which the electron is bound. So you can definitely calculate that.
You can ignore relativity, you can include relativity or whatever.
But in order to trap that electron forever so that
there's no chance it ever leaves, then you essentially need
an infinitely powerful electric force. You need an infinite amount

(41:51):
of charge to trap an electron that could effectively have
infinite energy.

Speaker 6 (41:56):
So would that mean that my electric black hole is
infinitely or infinitely small.

Speaker 1 (42:04):
It would be infinitely charged.

Speaker 6 (42:06):
Oh does it have to be infinitely charged or could
it just be a charge but infinitely dense.

Speaker 1 (42:11):
You might imagine bringing the electron like really really close
to that charge so that the electric force gets really powerful,
because the electric force also gets powerful as things get
really close together. But again, these are quantum objects. There's
always like a minimum effective radius. It's not really an
orbit but this is like a mean distance from the
center for the ground state, and so that effectively limits
how powerful these things can get. Like there's a reason

(42:34):
the hydrogen atom has a ground state and the electron
is not closer to it. It can't settle any closer,
and that effectively bounds like how strong the force can get.

Speaker 6 (42:44):
Oh Man, So you're saying quantum mechanics ruins all the time.

Speaker 1 (42:49):
Like usual, But you also have another question about like
why can't we describe the other forces in terms of curvature?
And there are people working on that, people wondering like, well,
what if electromagnetism actually is curvature but not in our
three D space? What if it's curvature in like additional
spatial dimensions. And nobody's really made that theory work, but
it's really fun to think about how electromagnetism might be

(43:11):
like curvature in other ways that we can't see it yet.
And even in that theory, you might be able to
describe electromagnetism as curvature, and you might wonder like can
I make event horizons in those other dimensions? But then
you wouldn't be making event horizons in our three D space.
Which I think is really what the question was.

Speaker 6 (43:28):
So then it would be sort of like a black hole,
but in other dimensions.

Speaker 1 (43:31):
It's pretty hard to think about, but it would be
curvature in other dimensions, and you might have event horizons
in those dimensions, but not in our dimensions, so pretty
wonky stuff.

Speaker 6 (43:40):
There'd be holes in our black hole is basically.

Speaker 1 (43:42):
What you're seeing.

Speaker 6 (43:43):
Yeah, exactly, all right, Well that's an interesting answer for Derek.
Now let's get to our last question of today, and
it's about the air we breathe and where does part
of it come from? So let's dig into that question.
But first let's take a quick break.

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(45:08):
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Speaker 6 (47:27):
We're answering listener questions here today, and our last question
comes from Steve Parrin from Quebec.

Speaker 5 (47:33):
Hi, Daniel and Jorge, this is Steve Pagan from Quebec, Canada.
My question is where is all the nitrogen in our
atmosphere coming from?

Speaker 1 (47:44):
And what role does it play? Amazing podcast guys, I
love it, Thank you?

Speaker 6 (47:49):
All right, A pretty straightforward question here, Where does all
the nitrogen in our atmosphere come from? And what role
does it play?

Speaker 1 (47:57):
Yeah, nitrogen is a big deal on Earth. Like most
of the atmosphere is nitrogen. You take a deep breath,
you think yourself as like gulping oxygen, but it's mostly
nitrogen that you're breathing in, which is kind of weird.

Speaker 6 (48:10):
WHOA, what do you mean mostly? What are the percentages?

Speaker 1 (48:13):
It's almost eighty percent of the air is nitrogen.

Speaker 6 (48:16):
Eighty percent by like a volume mass or atoms.

Speaker 1 (48:20):
It's seventy eight percent by mass.

Speaker 6 (48:23):
Oh, and how much of it is oxygen? So it's
like most of the air is nitrogen.

Speaker 1 (48:27):
It's seventy eight percent by quantity.

Speaker 6 (48:30):
Meaning by volume or what do you mean by quantity
like number of atoms?

Speaker 1 (48:34):
Yeah, like number of molecules. Actually, if you count it up,
if you take like a cubic meter of air and
you count all the molecules in it, seventy eight percent
of those are nitrogen and twenty one percent of those
are oxygen.

Speaker 6 (48:45):
WHOA, no hydrogen.

Speaker 1 (48:47):
There's almost no hydrogen in the atmosphere because it's very volatile.
Any hydrogen will react with the oxygen and make water.

Speaker 6 (48:53):
So where did all this nigrogen come from?

Speaker 1 (48:55):
Yeah, it's a really fun question. It goes back to
the whole origin of like why we have an atmosphere
in the first place, because it's kind of weird. You
know that we have enough gravity to like hold this
little super thin envelope of gas around the planet, And
if you think about how the planet came to be,
it's not clear, like why we have an atmosphere that
survived the formation of the Solar System, because as things

(49:18):
were condensing very early in the Solar System, it was
a very volatile place. Like first of all, we're in
the Inner Solar System, which means we're pretty close to
the Sun, and so most of the hydrogen in the
Inner Solar System was gobbled up by the Sun. Like
the Sun has huge gravity. The reason that Earth was
formed is because it's not hydrogen. It's because it's rocky,
had like enough gravity to form its own little gravitational

(49:41):
well and cluster stuff together before it all got gobbled
up by the Sun. But that tends to gather together
heavy things like rocks and metal, right, chunks of iron
floating in space, not clouds of gas, most of which
fell into the Sun. Some of it did form with
the Earth, but then when the Sun started fusing, it
created all this intense radiation and lasted away our atmosphere.

(50:01):
So we might have had like a very thin hydrogen
atmosphere to begin with, but then most of that got
lost due to the solar radiation and then also collisions
by heavy stuff, like the formation of the Moon was
due to this collision with a protoplanet and that probably
destroyed all the atmosphere we had initially.

Speaker 6 (50:20):
But I guess a deeper question is where did it
all come from originally? Like it just got form inside
the Sun like all the other heavy elements in previous
iterations of the Sun or supernova or what.

Speaker 1 (50:33):
All the nitrogen and everything in our Solar system that
isn't hydrogen was not made by our star, right, All
that was made by previous stars. So like the deeper
history is that we have mostly hydrogen formed in the
very very early universe, tiny tiny trace amounts of helium,
and then you have to wait for stars to be
born hundreds of millions of years later to turn that
hydrogen into heavier stuff. And so that nitrogen that you're

(50:55):
breathing right now. Was made at the heart of stars
previous generation, which burned created that nitrogen inside them, and
then blew up and spread those heavier elements, including nitrogen
and iron and copper and on carbon and all that
good stuff throughout the galaxy, and then that re coalesced
into our solar system. So all the nitrogen and the
iron and all that stuff in our bodies and in

(51:17):
the air and in the Earth was made by a
different star that no longer exists whoa.

Speaker 6 (51:23):
And it was made at the core of that previous star,
or when it exploded.

Speaker 1 (51:27):
The stuff that's iron or lighter was made to the
core of that star. It's made by fusion, because when
you fuse two lighter elements together, you release energy. But
that's only true up to making iron. Beyond iron, when
you fuse stuff together, it costs energy. So if a
star starts to do that, it begins to dim and
like steals away the energy. And stars need that energy
to survive because they're fighting against gravity. Gravity is trying

(51:50):
to compress them down into a black hole. And the
only reason the star survives for millions or billions of
years is that radiation pressure outwards. That's created by the
energy released by fusion. If that goes away, then the
star stars to collapse, and so stars can't make a
lot of the heavier elements above iron. For that, you
need either the death of the star, the supernova which
has super dense conditions capable of creating those heavier elements,

(52:14):
or things later on like collisions of neutron stars to
create the heaviest elements. But nitrogen is made in the
heart of those stars during normal fusion.

Speaker 6 (52:24):
So we're basically breathing dead stars.

Speaker 1 (52:26):
Every time you take a breath, it's a gift from
those stars.

Speaker 6 (52:31):
You're basically breathing zombie star.

Speaker 1 (52:34):
Yes, exactly, zombie star brains. Take a deep breath.

Speaker 6 (52:39):
Yeah, smells delicious, smells like brains. So the previous star
made the It was floating around just like all the
hydrogen and carbon and dust and rocks that was made
by previous stars when our Sun started burning, And then
how did it end up on Earth or is it
spread out all around the Solar System.

Speaker 1 (52:59):
It's all over the sol System. Nitrogen is everywhere, It's
not just on Earth. And the nitrogen in our atmosphere
ended up on Earth in an interesting way. Number One,
it came from the bombardment of the Earth by like
comets and asteroids that had like frozen nitrogen in them,
and so we think, like a lot of the water
on Earth may have come from comets. The same thing

(53:21):
is true of nitrogen. So the early Earth was blasted clean.
Essentially it was just a bare rock because of the
solar radiation. But then it got a second atmosphere due
to collisions and also because of nitrogen and other gases
trapped inside the Earth which escaped out due to like volcanoes.
You know, you have a lot of these gases in
the early Earth, and as the Earth is settling, the

(53:43):
heavy stuff goes down to the core and the lighter
stuff rises in the mantle, and then some of that
escapes through cracks in the Earth. So volcanoes and the
bombardment of asteroids created our second atmosphere, which was mostly
nitrogen and carbon dioxide. So that's where the nitrogen comes.

Speaker 6 (53:59):
From, and then eventually we got oxygen. But I guess
the second part of the's question is what role does
nitrogen play? Like do our bodies need nitrogen or do
we just ignore it? Mostly?

Speaker 1 (54:13):
Yeah, it's definitely not inert. Nitrogen plays a really important
role in the life cycle here on Earth. Like plants
need nitrogen. It's a crucial part of a lot of
amino acids, and so in order for plants to grow,
you need nitrogen in the soil, a big component of
like fertilizer that people are constantly putting onto their plants.
Farmers impour huge amounts of it. The reason you put

(54:35):
manure on fields is that it has nitrogen in it
and other stuff. So plants need this nitrogen in order
to grow. And there are these bacteria that will breathe
the nitrogen from the atmosphere and then basically make it
available for the plants. So there's a whole complicated nitrogen
cycle that involves like these nitrogen fixing bacteria and then
plants using it to grow, and animals eating it and

(54:56):
then pooping it back out into the ground. And it's
very complex cycle, but it's definitely not inert. It's a
huge part of life on.

Speaker 6 (55:03):
Earth right right. And I just want to take a
quick moment here to note that you were the first
one to bring up poop in this episode, not me.

Speaker 1 (55:11):
Is that something you keep track of who says poop first?

Speaker 6 (55:16):
I'm just saying sometimes they get, you know, accused of
cultural language podcast down.

Speaker 1 (55:22):
Yeah, well, you know that's the conversation we have at
my house all the time because my wife works on
the gut microbiome, like literally, what's happening inside your guts?
And so the kids are always timing, like how long
till mom brings up poop at the dinner table? Oh boy,
and it's never very long.

Speaker 6 (55:38):
May should just call it nigrogen instead of poop nigrogen
rich content. They'll spare your appetites.

Speaker 1 (55:48):
We're just fertilizing a conversation.

Speaker 6 (55:50):
Yeah, you just want to make it more fregrant. But
I guess why is nigrogen important and biological processes? Is
it something there's something special about that molecule, you know,
because carbon as some special things about it that make
it kind of crucial to life? Is legigend similar?

Speaker 1 (56:06):
Well, I think you're getting pretty deep into the chemistry here.
You know, the amino acids are the basic building blocks
of life, and having different kinds of atoms there, it
gives you different options, different things you can build. But yeah,
dot dot dot chemistry. I guess to be a Wikipedia later,

(56:27):
I mean, na gigen is already at the edge of
my ability to think about things. There's so many protons
there it's crazy. And then you have it connected with.

Speaker 6 (56:36):
Another chem your brain would explode.

Speaker 1 (56:38):
Yeah, exactly, too many integrals from me.

Speaker 6 (56:41):
For as a physicist zombie. You just have to throw
some chemistry questions at them, absolutely, and then their brains
will explode.

Speaker 1 (56:48):
Yes, chemistry is our kryptonite for sure. And they don't
even have to be that hard, just like my high
schoolers ap chemistry questions. Whoa headache?

Speaker 9 (56:56):
Time?

Speaker 1 (56:56):
Right?

Speaker 3 (56:57):
Right?

Speaker 6 (56:57):
Hey Daniel, what's up? Regardless number big Welcome to Jorge
explains the universe. All right, Well that's the answer for Steve,
which is that the nigogen we're all breathing, eighty percent
of the air we're breathing, came from a debt previous
star in our solar system. Then it got formed with

(57:19):
the rest of the Earth and the rocks and the
other elements, and that's how we're breathing it today. That's right,
Possibly from comets, possibly from the Earth burping.

Speaker 1 (57:29):
Yeah, exactly. And there have been some people doing really
interesting studies to try to understand exactly where this nitrogen
came from, because not all nitrogen is the same, some
of them have different isotope ratios, and you can tell
like was it formed in the Outer Solar System or
the Inner Solar System the molecules not the pure nitrogen
which was made in the stars. And so there are
these studies that tell us that some of the nitrogen

(57:50):
on Earth came from the Inner Solar System and some
definitely came from the Outer Solar System. So it's a
similar question to like where did our water come from?

Speaker 6 (57:58):
All right, well, three awesome quiesce here today. Thanks to
all of our listeners who sent in their questions.

Speaker 1 (58:04):
And thanks to everybody who asks questions. Please don't be shy.
Write to us two questions at Danielanjorge dot com. You'll
definitely hear back from us.

Speaker 6 (58:11):
We hope you enjoyed that. Thanks for listening, See you
next time.

Speaker 1 (58:20):
For more science and curiosity, come find us on social
media where we answer questions and post videos. We're on Twitter, Discorg, Instant,
and now TikTok. Thanks for listening and remember that Daniel
and Jorge Explain the Universe is a production of iHeartRadio.
For more podcasts from iHeartRadio, visit the iHeartRadio app Apple
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