A separate problem is, miners in space, mars or the moon would have a hard time getting blocks into the chain since Bitcoin is a time-stamping machine and the longest chain wins. If it takes information too long to be disperses through the gossip network, EVEN IF YOU WIN A BLOCK it'll be invalid.
This would also make getting txs into the mempool a bit harder as you'd have to put a higher fee to anticipate fee price jumps by the time the tx arrived into the mempool since there would be a delay from the price you see for miner fees and the real price once your tx arrives to the majority of miners.
This problem is biggest on other planets, less so on the moon.
Basically earth will have a monopoly on mining.