Perhaps I'll get around to describing the cats of other worlds as part of describing the Old Solar System setting.
Cats from Venus
Old Solar System Venus is a rainy world of alien swamps and dense jungles; there would be cats evolved to live both in the Venusian Dreamlands, and on waking Venus.
Cats from Jupiter
Dark and joyless varieties of cat might exist on one or more of Jupiter's moons, while strange and alien cats prowl the cool, dark and gelatinous world of Dreamlands Jupiter itself. Jupiter's bitter and alien moons are not attractive worlds for ordinary cats, and one suspects that these moons hold little or no lure for Earthly cats, and likewise have little attraction even for the Dreamlands cats of the outer worlds of Saturn and beyond, as even those peculiar examples of the feline race are said to prefer the moons of Earth and Mars among all other moons for whatever cryptic charms have always attracted cats to make their lunar pilgrimages since time immemorial.
Cats from Neptune
Neptunian cats are probably very similar to the other bizarre and dangerous cats from the outer worlds, resembling the Dreamlands cats of Saturn, Uranus, and Jupiter. These vast, dark, and icy worlds seem to have attracted cats of very curious, secretive, unfriendly, and even sinister and malevolent temperaments, and, no doubt, the rarely-seen Neptunian cats are no exception to this general rule. Who can say what awful mysteries and hideous secrets of the dark, swollen and cthonic outer worlds are kept and guarded by the silent and sinister cats of Neptune and beyond?