I learned growing up that gas giants like Saturn and Jupiter are mostly gas. What does that mean exactly? Do they have a ground/crust or is it just gas all the way through?
In: Physics
We don’t know for certain, but basically it starts out as a thin gas at the “surface”, and as you go deeper, it becomes thicker, and if you go deep enough, there’s so much pressure from gravity it condenses into a liquid. So there’s an ocean of hydrogen down there somewhere.
It’s speculated that there *might* be a small rocky core, but it’s mostly just gas: about 90% hydrogen and 10% helium with a tiny amount of other stuff mixed in.
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