Distance from the sun is a huge issue with regards to whether you can have water laying around. From Jupiter's orbit out you often have tons of water on the su

Distance from the sun is a huge issue with regards to whether you can have water laying around. From Jupiter's orbit out you often have tons of water on the surfaces of moons with no atmospheres. Where Ceres is it looks like water sublimes but not too quickly, so that patches of ice exposed by collisions last long enough for us to see them.