I mean by this is there a bottom on a gas planet that we can stand on?
Or is there no bottom there and we just can’t stand on a planet like Saturn and Jupiter? Because, for example, you can stand on Mars and on some other planets you can’t stand on a gas planet? How about that?
Thanks in advance Gilles.
Answer
The gaseous planets Jupiter and Saturn have a rocky core surrounded by a mantle of liquid metallic hydrogen, which makes up most of the planet, followed by a layer of molecular hydrogen. There is an atmosphere around it. The other two gas planets (Uranus and Neptune) also have a solid core, but they lack the mantle of liquid metallic hydrogen.
see for example :
http://lasp.colorado.edu/education/outerplanets/giantplanets_whatandwhere.php
The difference between a gas planet and a rock planet has to do with the place (ie the distance from the sun) where they originated as a planet. A few days/weeks ago a question was answered on this website by prof. Waelkens about the origin of gas versus rock planets: question 19044 />
Answered by
prof.dr. Paul Hellings
Department of Mathematics, Fac. IIW, KU Leuven
Old Market 13 3000 Leuven
https://www.kuleuven.be/
.