The biggest collisions in the Universe

Bonus episode: Daniel and Jorge visit the metaverse to discuss what happens when particles, stars, galaxies or superclusters collide!

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Episode Transcript

Speaker 1 (00:00):
Hey everyone, Daniel here, we have a little bit of
a special treat for you today. Earlier this year, Jorge
and I recorded a special episode with audio and video
for premiering in the Metaverse, and today we are bringing
it to you on the feed as a special bonus episode.
It's a bit different from our usual episodes, but we
thought you'd enjoy it. Thanks for listening. Hey, Jorge, is

(00:32):
this the way to the metaverse? I met a donna?
Where is the metaverse? I don't know. I was supposed
to meet you there to do an episode. Are we
in the right place? Let me see every saying. We're
inside of simulation right now, this is a virtual conversation.
It might be a simulation within a simulation. That's so meta. Well,
that is the most interesting theory I've ever meta. Maybe
in the end, none of it really met us. Hey,

(01:09):
we made us to our land. On our podcast, Daniel
and Horrie explain the universe. We like to talk about
planets and galaxies, but we never thought we'd get to
do it from another world, and here we are in
our heart land. How cool? Is then? So cool? Now?
On our podcast, Jorge and I typically talk about some
of the biggest most amazing unanswered questions in the universe,

(01:30):
and today we have some really fun stories about the
biggest collisions in the universe. Planets colliding with other planets,
stars colliding with other stars, even galaxies hitting other galaxies.
But before we start, we want to give a shout
out to our partners State Farm and of course Fortnite
for having us here. Hi'm Ho I'm a cartoonist and
the creator of PhD comics. Hi I'm Daniel. I'm a

(01:51):
particle physicist and a professor at UC Irvine, and I
love to smash things together to figure out what they're
made out of. Welcome to our podcast. Daniel and Horta
explained to universe in production of our heart Radio, in
which we try to smash your brain together with the
whole universe. We think that there are so many interesting
things to understand out there. We want to bring your
brain together with all of those questions and give you

(02:13):
some understanding of how things work. So today we'll be
breaking down some of the biggest collisions in the universe.
You know, that's kind of a tricky word to these
biggest because especially in physics, that can mean a lot
of things, Like you can mean biggest in size. It
can mean biggest in speed, or biggest just in terms
of the impact that we have on our planet, or
biggest in drama. Right, we do for drama. So what

(02:39):
would you say are some of the biggest collisions in
the universe. Well, we do some pretty fast collisions here
on Earth. We accelerate protons to almost the speed of
light and smash them together underground in Switzerland. So you
have a proton going in the speed of light this way,
proton going to speed of light this way. That's a
pretty dramatic collision. That's pretty big stuff. That's the biggest,

(03:00):
one of the biggest experiments humans have ever done. Yeah. Absolutely,
It's one of the most expensive and one of the
biggest experiments. So I'm here. I'm basically a shill for
big collision because it's my day job. And you said
you smash protons together, which is which are tiny little
particles that are part of the atom. So every we're
we're all made out of atoms, of course, and the
atoms are made out of stuff inside of them, including

(03:20):
electrons and protons. Yeah, so we take hydrogen, which is
a proton and electron, we pull away the electron because
we're not interested. And then we just smash the protons
the hydrogen nuclei together, and sometimes just like proton debris
comes out, and sometimes weird new stuff comes out where
any weird new stuff. But one of the amazing things

(03:41):
about collisions with particles is that what comes out doesn't
just have to be a rearrangement at what went in.
You can actually annihilate it and turn it into something new,
like a Higgs boson or a photon or a z
boson or something you didn't even know existed. Now, how
do you smash these protons together? You have like slingshots
to p pull back and they to scientists stand in

(04:02):
front of each other and then pull back and smash
the protests together. How does that work? That we take
the protons, we push them really hard with electric fields,
and then we bend them with magnets, so they go
around in a circle and we do that over and
over and over again until they're going really really fast
and we have another beam going the other direction, and
then we crossed them. So that's one of maybe one
of the fastest collisions that we know about as scientists

(04:23):
in the universe. And it's weird because we actually are
making that collision, but it actually doesn't even compete with
what the universe is already doing all the time. What
you mean, there are things in the universe smashing close
to each to each each other faster than twice the
speed of light. Absolutely, the universe is filled with huge
particle accelerators that are throwing particles at us that are

(04:44):
colliding with the Earth much faster than the particles are
moving in the Hadron collider. Okay, so that's maybe another
type of collision of things smashing together that we can
talk about is cosmic rays coming from space exactly. Cosmic
rays are a fancy word, but they just particles in
space zipping towards the Earth and then smashing in the
atmosphere like tiny little meteors. Now, these things normally would

(05:08):
be kind of dangerous, right like if you're hit by
even even though they're tiny particles, if it's going fast
enough and it hits it, it can actually kind of
um not be good for you. The atmosphere is like
a blanket that protects us. They hit the atmosphere and
they bounce against particles in the atmosphere and they lose
a little bit of energy by the time they get
down to the surface. Instead of having one particle with
a lot of energy, you have like trillions with a

(05:29):
little bit of energy. So we see these big showers
of particles hit the surface of the Earth. Alright, But
then it's a good thing we have our atmosphere to
protect us from these cosmic rays. It's like a dangerous Exactly,
if you're an atmosphere, you go out into space, you
really need to think about shielding because there's a lot
of crazy stuff out there in space. Maybe you think
about space as being empty, but really it's filled with

(05:49):
high energy particles whizzing all around. It's quite dangerous. Asteroids,
rocks from space that come flying towards the Earth, they
kind of get burned up in our atmosphere because they
hit that air and then they create all that friction
and then they burn up before they hit the Earth. Right. Yeah,
the atmosphere is like a big buffer, and if the
rock isn't too big or going too fast, then it
melts in the atmosphere, sort of the way like spaceships

(06:10):
when they re enter the atmosphere, they get heated up.
The same thing happens to asteroids and meteors that hit
the atmosphere. Well, but I just said, speed and energy
are really important, right, And sometimes we want to create
these collisions like once we talked about. I know you
were doing to study things and also what we observe
out up there in the sky, but sometimes we want

(06:31):
to create these collisions, maybe even to save the planet Earth. Yeah,
this is pretty cool. I don't know how many of
you know this out there. Put NASA, the Space Agency
of the US, has a program called the Planetary Defense System, right,
like that somebody's job is to literally like stand there
and be ready to save the Earth. I'm glad somebody's
doing it, because it's not my job. You're trying to

(06:53):
save the Earth on a daily basis, And so this work,
this happened recently. They send the what did they sound like,
a spaceship, like a little spacecraft, and then they just
accelerated it and aimed it towards this asterid. Yeah, the
spacecraft it's like the sizing weight of a refrigerator. So
they basically slammed a fridge against a big rock in space.
I like an ostril fridge. That would have been pretty cool.

(07:14):
I mean they stocked it first. You know, it's filled
with good drinks and all sorts of stuff like a
normal fridge. You know, it's like a huge cube of metal.
And they just slammed it right into the asteroid to
see if they could change its course and it did
right where was going before and they hit it, hit
it with the fridge spaceship and then they noticed that
the asteroid kind of change course. Right, Yeah, yeah, it

(07:36):
really did. So as a university professor, it's my job
to add a pop quiz to every situation. Well, ask
multiple questions and you answer by jumping on the square.
With the right answer, you get it right, you win rewards.
If you get it wrong, you'll get bounced out. Ready good,
because it's time for how fan are you? What happens

(07:58):
when black holes collide? It is it A, they explode,
b the universe ends? See you get one big black
hole or D. Nobody knows. The correct answer is c.
Nothing can destroy a black holes. They just get bigger

(08:20):
when they eat other things, including other black holes. So
we're talking about the biggest collisions in the universe, and
we talked about the fastest ones that we know about,
but you can also maybe think about biggest in terms
of like impact, right, like how it can affect us
here on Earth. Well, the Earth is getting hit by

(08:41):
this stuff all the time. We can't deflect all of it.
A lot of it gets melted by the atmosphere. But
in our history we have been smacked by some pretty
big asteroids. Like the dinosaurs were not as on point
as NASA is in terms of planetary defense, so they
got smacked by a pretty big rock about sixty five
million years ago. It killed off like fifty percent of

(09:01):
all the species on Earth actually in about an afternoon.
It would changed life on Earth forever, right, like we're
here because dinosaurs are not. That's right. It made room
for us mammals, So thank you alien asteroid tossers or
whoever is responsible for that had awesome theory. But then
asteroid by Throne was thrown by enemies of the dinosaurs species. No.

(09:23):
But one of my favorite theories is that they have
reconstructed the path of this asteroid before hit the Earth,
and they think it made two passes around and came
near the Earth before it actually hit, which means that
dinosaurs could have looked up into the sky and seen
it like ten years before it hit. The hit the Earth.
So they had their chance, right, they were warned, they
had their science together, they'd still be here, they'd be

(09:44):
doing this podcast instead of us. If that happened again,
would we be Do you think we'd be able to survive?
What do you think if like it gets past the
nasid defense system, it would be pretty challenging. What actually
happens depends a lot on where it hits. If it
hits in the water, then you're getting a lot of
vapor in the atmosphere. It hits on land and you're
getting smoke and getting volcanoes. None of that is going

(10:06):
to be very easy to survive. In order like remedy that,
you need planet wide geoengineering projects, and I just don't
think we're capable of today to start building those bunkers,
start investing and big beans. I hear those last a
long time. Question to what particles are collided in the

(10:29):
Large Hadron Collider A large hadrons, B protons, see photons,
D electrons. The correct answer is beat protons, which are
a type of hadron, and they're used in the Large

(10:51):
Hadron Collider. But that's also not the first time an
asteroids hid Earth. Yeah, we think there's a whole history
of these collisions dating back millions and millions of years.
But we also think that very early in the Earth's
formation there was an enormous collision. A whole planet hit
the early Earth. What Yeah, Actually, we do think that

(11:12):
there were other planets in the Solar System which got
ejected by Jupiter's gravity early on, kicked out of the
island off Jupiter. We're the survivor so far. But we
think that a Mars size planet probably hit the early
Earth and created an enormous collision, basically vaporized the whole surface,

(11:34):
and what came out of it turned into the Earth
and our Moon. So we're like, our Earth right now
is actually Earth two point Oh, it wasn't Earth before
that got obliterated and then it reformed again. That's the
Earth we have now, which you know feels like an upgrade, right,
I mean, I think it's pretty good. I got no notes.
So then a comet can hit a planet we saw,

(11:56):
we saw it in the nineties. It hit Jupiter, and
it could hit does And those are actually kind of
more dangerous, right, Those are more dangerous because comments go
really really fast because they come from much further away,
so they have more time to gather speed as they
come towards the Sun, and because they have long orbits,
you might not see them until they're basically headed right
towards you. Like, there could be comments out there right

(12:18):
now that take five years to go around the Sun
and we just haven't seen them yet. Now. I was
around in the nineties when that collision happened. That's when
the comments mashed into Jupiter. But I don't think I
was kind of paying attention. But you were. You were, like,
what else were you doing? Man? You were watching the
live broadcasts of it, right I was. I actually had
a telescope focused on Jupiter and I was taking video

(12:39):
myself because I wanted to see the explosion. Yes, at home,
you could you see it through the telescope like it
actually hit it, Like did it happened fast or in
the slow motion? It happened pretty fast and you can
see these fireballs be created. And each fireball is like
the size of the Earth. We're talking about incredible collisions here.
Fireball like it hits Jupiter, jupiters gas so that to

(13:00):
get into that. But when it hit Jupiter, it created
a fireball like that impact? Was that that? Yeah, there's
so much energy. Jupiter is basically a huge ball of
cotton candy, Like you're saying that, you hit it with
enough energy with a big enough rock, and the rock
gets vaporized in the atmosphere and you create a huge
ball of fire as big as the Earth exactly. So

(13:22):
we're sorry Jupiter, but we're glad it didn't happen us.
That would be bad. N Question three. What collided with
the planet Jupiter in a banana, B, an asteroid, c
aliens or z A comment? Correct Nassas D comment Shoemaker

(13:52):
Levy Clyde into Jupiter in alright, so that that's maybe
the biggest in the sense of the biggest collisions in
the universe. But we said we would talked about the
biggest collisions in the universe. Let's go bigger. Can you
smash stars together? Suns together? Now you've got the trick
of it, right, What would happen if you could smash

(14:13):
stars together? Right? Yeah, yeah, I'd love to see that.
It turns out that's actually quite rare. Our stars in
the galaxy are all swirling together around the center of
the galaxy sort of like a big lazy river. So
it's not very typical for stars to smash into each other,
but sometimes things do smash into each other. It does happen. Now,
what would happen actually happen if two stars collided with

(14:34):
each other. Yeah, it depends entirely on the velocity. If
they're going really fast, then they're going to obliterate each other,
just like what happened with proto Earth and the other planet,
like a huge spray of stuff. It's weird to think
about because we think you think of the Sun is
like a ball of fire, right, and so like if
you take two flames and you smash it together, nothing,
nothing really explodes. But the Sun is actually kind of

(14:56):
pretty neaty, right, Like there's a lot of mass in
the Sun, I mean, the almost all of the mass
in the Solar System, and it is stuff. I mean
it's on fire, but it is stuff. Yeah, it's a
huge ball of plasmids burning hydrogen. And the mass of
the Solar System is in the Sun. And so a
Sun's sun collision could obliterate both of them. It could
spray out a lot of this burning stuff, and the

(15:18):
temperature would be really incredible, so would be super bright.
Because what's happening inside the Sun is fusion to create
all that light, and that pressure and temperature would make
a fusion happen to like a super charged rate. It
would be like much brighter than the Sun has ever been. Wow.
So it would you basically see a giant spark from
the collision, and then it would spray out and then

(15:38):
it would turn off, or with this cloud of stuff
debris keep burning, it would go out right, the cloud
of debris would probably reform back into either one big
star or two smaller stars, but it would take a
little while, would take you a few hundred million years
probably the recoalesce into something else that could burn. Right,
let's go bigger, Daniel, what happened can be bigger than

(16:00):
two stars colliding. Well, instead of just colliding one star,
what if you collided like whole groups of stars? Right,
a group collision? Okay, are you talking about like colliding galaxies? Yes, exactly.
Let's go really big. So like our galaxy, the Milky
Way has hundreds of billions of stars in it, and
the neighboring galaxy and Drameda is even bigger. It's much

(16:22):
more massive than our galaxy, and it's headed right for us. What, Yes, exactly,
somebody throw it out us. There's another conspiracy, conspiracy theory.
If the light rate didn't work, if the astars didn't work,
Now they're throwing a galaxy. Somebody is just making sure
there's a lot of drama in the universe. Right, We've
got lots of sequels lined up. Two, three, four. Question four,

(16:47):
what galaxy will collide with the Milky Way in four
and a half billion years? A Candice Major B, the
peanut butter galaxy, c Omega or D and draw amada.
The correct answer is the Andromeda will collide with our

(17:10):
galaxy in four and a half billion years. But the
good news is that the collision will not actually be
that dramatic. Okay, so the whole galaxies colliding, that's not
that exciting, you're saying, because galaxies are actually kind of empty. Right.
They're big, they're big, they're bright, but they're like kind
of like clouds almost like they're not that meaty. Yeah, exactly.

(17:34):
It's like throwing two handfuls of sand towards each other.
Mostly the sand doesn't hit other bits of sand. Mostly
they just miss. Can we go bigger than you can?
These mass things that are bigger than the gust of
course you can, and of course you can always go.
There's still limits science, and this is where you go.

(17:55):
But it's part of a big group of galaxies that
I'll orbit each other. So it's like a big object
that's gravity deciently bound together. It's the cluster of galas
cluster of galaxies that's like a lot of galaxies are
kind of moved together exactly. Gravity is holding them together.
And then the universe is filled with these clusters of galaxies.
Do we know if our cluster is heading towards a
collision with another cluster? Do we know that? Or is

(18:17):
it just inevitable? It's just inevitable. Eventually you're going to
bump into somebody else. Yeah, just like the Milky Way
and Andromeda. The universe is trying to push them apart,
but gravity is so strong between them that it's pulling
them together, so that eventually they will collide. Can we
go bigger than you? What? What's the biggest thing we
can let's just wrap this up. What's the biggest thing
we can collide that we can smash together in the universe.

(18:39):
So galaxy clusters organize themselves into something we call superclusters,
which basically like clusters of clusters, and these are huge
enormous things, like mind bogglingly big, like five hundred million
light years across five hundred million, so like a ray
of light would take five hundred million years just to

(18:59):
like go from one side of the ing. This is
like a pretty big chunk of the universe. So we
call this a supercluster. And we're part of a supercluster,
of course, and so superclusters can smash into each other, right,
And we actually think that our superclusters is sort of
headed towards another supercluster. Really, we can track it. We
can track it is this thing out there called the

(19:19):
Great Attractor, which is a huge source of gravity far
out past our galaxy. We don't understand it. We don't
really know what's going on, but we notice everything is
moving towards it, and other superclusters are moving towards it.
So like deep in the future supercluster collision, oh man,
And it's all being pulled together by a mysterious force, right, Like,
we don't know what it is. We can't see anything

(19:40):
there that's pulling these things. We think it's probably gravity,
but we can't see what's causing that gravity. So Yeah,
we don't understand what the great attractor is? Question five?
Where is Daniel a professor? Is it a U c
Irvine b UZ Berkeley ce Universe University or d sir

(20:09):
great aspect ay you see, Irvine Daniel is a professor
of physics at the University of California Aderba University University.
Right now, the universe is kind of, like you said,
organizing galaxies and clusters and super clusters, and these are

(20:30):
like form kind of like like branches out during the universities,
everything s matches together. Does it all become like a
giant ball of stuff or like a giant black hole
or like a giant star? You know, like what's the
eventual uh uh, you know event there were consequence of
two of these giant things smashing. Yeah, what's the ultimate
spoiler of the universe? Well, you've got two big forces

(20:52):
a play. You have the universe trying to pull itself apart.
Dark energy is like accelerating everything further and further apart.
Do you have gravity pulling itself together? The question really
is like how much gravity pull stuff together before dark
energy tears everything apart? Because the far future is we
have these like islands of stuff separated by space, and
so gravity is like trying to gather as much together

(21:12):
as possible before the universe tears it apart. So all
this stuff is going to end up in a super
black hole eventually. What Yes, So all this stuff that's
close to us will eventually smash together, saying like that
that's inevitable in a way, will form tiny black holes,
and then those black holes will crash into each other.
That's another interesting collision, black hole on black hole. Yes, exactly,

(21:36):
we've seen that happen already, black holes hitting each other,
swirling around each other and creating bigger black holes. They
make these amazing ripples in space time. But that's the future.
Everything falls into a black hole, which is then separated
from the nearest black hole in the universe, keeps those apart.
But everything in our little like sort of gravitational well
nearby is going to end up inside that black hole.

(21:57):
Oh cool. Well, like you said, I think that watching collisions,
thinking about collisions, imagining collisions, sometimes simulating collisions is a
big part of how we understand the universe, right, because
that's kind of how you test things and see what happens.
That's how that's how you learn how things actually work. Yeah,
you can see what's inside stuff, you can see how
they react with each other. These are great experiments for

(22:20):
understanding the basic nature of the universe. So that's why
we do the underground on Earth when we can, and
we watch them in the sky when they happen for us.
That's how you crack open the secrets of the universe. Yes,
exactly together. Yeah, that's when the spoilers all come out, right,
So that's when we're paying attention I see from the drama,
because I guess you can just ask the universe how

(22:41):
it works, do you get to Yeah, you learned from
the drama. Well, I've been asking, but nobody's answering. It's
like a mystery, right, You just got to pay attention
to the clue. It is a big mystery, the universe,
and we are slowly learning more and more about it
every day thanks to scientists and thanks to uh good
Thanks smashing into each other. Thanks everyone for joining us

(23:01):
on this episode of Daniel and Jorge Explain the universe
and keep asking your own questions about what's out there. Yeah,
we hope we smashed your brain with some new knowledge
and blew your mind or not or just merged it
with a little bit more with the Cosmos and the Universe.
Thanks for joining us, see you next time. Thanks for listening,

(23:28):
and remember that Daniel and Jorge explained. The Universe is
a production of I Heart Radio. For more podcast for
my heart Radio, visit the I heart Radio app, Apple Podcasts,
or wherever you listen to your favorite shows. Yeah.