Eleven times wider than Earth.
Over 300 times more massive.
And a million times
more terrifying.
Jupiter looks like a beautiful ball
of swirling clouds,
but on the inside,
it's a gaseous hell.
What if things took a different
turn for the king
of the Solar System?
What if Jupiter wasn't
a gas giant at all?
What if, instead,
it was a rock giant?
What would its surface be like?
What could make this
world habitable?
And what would happen
if you tried to walk on it?
This is What If,
and here's what would happen
if Jupiter was a rocky planet.
Jupiter is old.
Like four and a half
billion years old.
It started as a swirling
disk of gas and dust
that formed
into a pretty big planetary core.
With time,
Jupiter's core grew
attracting more and more rock,
ice and metal.
But Jupiter
wasn't going to become
a rocky planet.
No.
It had an enormous appetite
for gas.
Yeah, Jupiter's powerful
gravitational pull
drew in massive amounts
of hydrogen and helium
that shaped it
into the majestic gas
giant we see today.
But what if
things went differently?
You know,
what if?
What if, instead of gas,
Jupiter kept
pulling in more rocky materials
until it became the most
massive terrestrial world
in the Solar System?
Would that be the end
for everything
in our planetary neighborhood?
Just like our cosmic journeys
in What If videos,
you can embark on a mind journey
that's both free and accessible.
You can do it with our sponsor,
Brilliant.
If you love What If,
you're going to love Brilliant.
It uses interactive,
hands-on learning to explore
topics like math,
data science and computer science.
It's for people like you,
curious explorers
who want to sharpen their skills
and even help get a career boost.
What I like about Brilliant
is how it tailors
the learning experience
to my level and pace.
I've recently been
enjoying their course
on astrophysics,
and at times
it feels like one of our videos.
A thrilling expedition
into the complexities
of the cosmos.
But it always feels accessible
and approachable.
So give Brilliant a shot.
You can start your learning journey
for the first 30 days
completely free.
And you get 20% off
by going to brilliant.org/WHATIF.
Link in the description.
For this Jupiterocalypse,
we’ll keep Jupiter's size
just as it is today.
Only now, all rock, no gas.
Jupiter would become
unimaginably massive.
This world would be four times
heavier than its gas giant form.
And keep in mind,
the gas giant Jupiter
is already about twice as massive
as all the other planets
in the Solar System combined.
And with this enormous
mass would come unimaginably
strong gravity.
Rocky Jupiter's
gravitational pull
would now be four times
more powerful than it was before.
And that's about ten times stronger
than the gravity
you and I live with here on Earth.
Yeah,
you wouldn't be able to walk
on this rocky Jupiter.
Your body would experience
a gravitational pull
so extreme
that it would break your bones.
Your heart would beat
out of your chest working
so hard to pump your blood.
And as your blood
pooled in your lower body,
you'd feel dizzy and lightheaded.
Well, you may not want to
walk on this Jupiter anyway.
The rocky
king of the Solar System
would now attract
even more moons and asteroids.
And some of them
would be on a collision
course with the rocky giant.
But what would its
surface be like anyway?
Well, apart from the constant
asteroid collisions,
it could be a pretty nice
place to visit.
If you could walk there,
of course.
Rocky Jupiter
would still lie outside
the Solar System's
habitable zone.
But this doesn't mean
it would be a frigid world.
Jupiter is gigantic.
And rocky Jupiter
could retain a lot of internal heat
from when it formed.
So even though it's much further
from the Sun than Earth,
rocky Jupiter
could have surface temperatures
similar to our planet.
It might even have hot oceans.
Terrestrial Jupiter's gravity
might cause the planet
to have a very thick
atmosphere, and worlds
with thick atmospheres have,
yeah, high atmospheric pressure.
That means that
the boiling point of water
on this rocky
giant would be higher
than it is on Earth.
And the oceans could be as hot
as 200 °C (390 °F),
and still remain liquid.
Yeah, we're
not going swimming there.
Even if you could
somehow walk on this world,
you wouldn't want to breathe on it.
Gas giant Jupiter's
atmosphere is mostly hydrogen
and helium.
So if the rocky Jupiter's
atmosphere was also
made of hydrogen and helium,
it wouldn't be breathable.
Then there would be
the lightning storms.
Yeah,
Jupiter already
has massive storms
in its clouds,
and rocky Jupiter
would be no different.
If this planet also had active
volcanoes spewing
ash and lava, well,
that would make the
lightning storms even more intense.
Volcanoes could be good news
for the rocky world, though.
The gases
they release
might change the atmosphere
of rocky Jupiter
and make it habitable.
And if not for you,
maybe for some other life forms.
And those other life forms
could be terrifying.
They might be bigger
and stronger than dinosaurs,
just to withstand
Jupiter's enormous gravity.
Or they could be tiny microbes
living under
rocky Jupiter's surface.
But, obviously,
that's a lot less exciting.
The thing is,
Jupiter's increased gravity
would push our planet
out of its stable orbit,
and that would dramatically change
our climate.
Earth could be pushed
closer to the Sun,
turning this place
into a hot, hellish world.
Or we could be driven
further from the Sun
and freeze over.
Either way, it's bad news for you.
And Earth
wouldn't be the only planet
pushed out of its orbit.
Everything in the Solar System
would plunge into chaos.
Planets and moons
would be knocked off course,
some of them
colliding with each other.
Things would get messy.
You could only hope that nothing
would crash into Earth.
But you know what?
Things could be worse.
Like if Jupiter was
on a collision course with us.
Well, that sounds like a story
for another WHAT IF.
Oh, and one more thing.
We here at
What If are on a mission
to reach 10 million subscribers
by the end of the year.
Only you can help us get there.
Let us show you the worlds
you've never seen before.
Hit like and subscribe,
and remember
to tell your friends about us.
By the way, whoever's left,
congratulations on
surviving this episode.