[1.187] Jumping to a GPS coordinate on a planet places you within the gravity well
So this just happened on one of Keen's official servers (World NA #11, Per Player PCU).
I attempted to jump to a coordinate on the moon, and after the jump ended, I was spawned on the moon with my ship nowhere in sight. I can still spawn in my medical room, but it just places me back on the moon at the same spot.
A friend was jumping to my base (~10km outside of Mars' gravity well) and his ship ended up 9km above the surface. He promptly crashed.