Dupes sent into space are considered not in the simulation, so there are code problems when the game tries to interact with them.
I've found a couple of ways this can happen by accident so far
1. When your dupe takes an atmo/jet suit with them into space, if you click on an unused atmo/jet suit you can click to have them remove their suit, which crashes the game. I imagine the same would happen if you tried to have them equip a suit while in space using the same method.
2. *FIXED* (noticed another post about random crashing that was this error I believe) When your dupe takes a Balloon with them into space, when the balloon buff expires, the game attempts to interact with the space-bound dupe and crashes.
3. Not sure where else but I suspect there are other places where buffs are wearing off perhaps <3