What happens if a network “splits”
The chain would split and when the networks re-connected the longer chain would take precedence.

All transactions on the orphaned chain from the time of the split would be invalidated. Good if you were a spender, bad if you were a receiver.

Note that one company in particular has already deployed a satellite system that broadcasts bitcoin blocks. If there were nodes on both parts of the network receiving the satellite broadcasts when the "split brain" occurred they would be able to keep it from forking, at least that's the theory.