Moons invisible "ground"

[raidernick]

This is the same issue I had mentioned a while ago regarding some of the moons and an invisible surface. For instance, on triton when you pass the 1.5km threshold above the ground any parts you decouple from your ship will go "down" then suddenly fly back up again and freeze at 1.5km in the sky while your main ships lands on the actual terrain. This happens on all of the galilean moons, triton and titan. I haven't tested with others but i'm sure they all have the same issue.

@NathanKell had mentioned knowing of this issue for a while and I thought had implemented a fix several versions ago but the problem is still there. I see the old issue is still open here: #22