Jupiter is the largest planet in the Solar System (mass 318 x Earth's; diameter 11 x Earth's).

The surface is covered with a thick atmosphere of H, He, CH₄, NH₃, and some H₂O.

There is a probably a rocky core deep in the interior of the planet that is surrounded by high pressure H (in a liquid-metallic state). The temperature increases with depth, and so organic molecules can only exist in the upper layers.

The bright colors of Jupiter's clouds suggest that organic molecules are present (such as CO, HCN, C₂H₂, C₂H₆). The chemical environment is probably similar to that of Earth's early atmosphere.

Life could exist in the clouds of Jupiter, but it would be difficult to sustain because of the low gas densities and the circulation currents (which take molecules to deeper levels where organic molecules break up).