So I have noticed that randomly there are lots of spots in the ground where the surface has not loaded correctly and you can plumit into the earth. When this happens with your astronaut is seems to force the astronaut back onto the surface BUT with a rover you will be driving along and boom fall through the earth. I took i video of me and my rover having plumitted to the center of the planet and just kept falling up and down in the middle of the planet. Once I exited the vehicle my astronaut (but not my rover, it is still stuck in the center of the planet never to be heard from again) was slow