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dickbutt_md t1_j5m2vb1 wrote

I wouldn't consider a solid core to be a solid surface, though.

This is a semantic distinction, though, at this point we would be arguing about what to call whatever is there, not a disagreement about what is actually there.

Though I'd prefer to distinguish between the core and the "surface" such as it is, I do think there's a reasonable argument to be made that "surface" should be identified as "whatever is solid." The problem with this terminology is that it doesn't really recognize any difference between gas giants and rocky planets, which I'd argue is a useful thing to do.

But, when it comes to what's actually there, I think we agree.

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DukeElliot t1_j5mbi1e wrote

There is a sentence in that article that says “While some theorize that the core is a hot molten ball of liquid, other research indicates that it could be a solid rock 14 to 18 times the mass of the Earth” referring to the core

Would “solid rock” not mean a solid surface in this context?

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Bipogram t1_j5mhk4m wrote

Over which is an ocean of hypercompressed hydrogen at essentially the same density as the rock below.

The only transition is one of composition (mumble: and both seismic speeds) rather than density - which we seen in the terrestrial oceans.

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ghostoftheai t1_j5neitn wrote

So if it’s as dense as rock can you walk on it or is that not how it works?

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Bipogram t1_j5p5m64 wrote

We can walk on things because they're rigid solids.

But I doubt that there's a nicely defined discontinuity between the metallic hydrogen ocean and some rock.

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dickbutt_md t1_j5nsyid wrote

The surface of a gas giant is defined separately from the core, as the article says: "...there is no solid ground, the surface of Jupiter is defined as the point where the atmospheric pressure is equal to that of Earth."

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