[jessriedel]

As others note, the definition of Jupiter’s radius is set by where the pressure is 1 bar. This is somewhat arbitrary, but the arbitrariness doesn’t matter much: the pressure drops to 1 microbar just 320 km higher, which is <0.5% of Jupiter’s ~70,000 km radius.

[gus_massa]

For comparison, extracting the numbers from the graphic in page 3 of https://projects.iq.harvard.edu/files/acmg/files/intro_atmo_... 1 microbar on Earth is like 50Km, that is 50/6400 ~= 0.8%

[queuebert]

Venus would get a slight radius buff, too, if we applied that metric.

[hnuser123456]

But Venus has a solid surface.

[queuebert]

Yes, that's why I said buff. The radius as defined would increase, because surface pressure is 90 bar, so at 1 bar, you're pretty high in the atmosphere. I can see merit in such a definition because that is the level at which we wouldn't have to pressurize our space stations to be comfortable. (Really 1/3 bar is fine too.)

[hnuser123456]

Ah, I see what you're saying, didn't know the surface pressure was so high! I suppose Titan would also get an atmosphere radius buff!