Bitcoin will cause a huge split in the market, and possibly lead to a full-scale nuclear world war, when the Bitcoin block chain on the Mars colony permanently forks from the Earth one due to the 15 to 30 minute communication lag, leading to double-spending, loss of faith in the currency, and vastly increased tensions between two already strained political entities. Satoshi should've foreseen the 10 to 20 minute one-way radio transmission time issue when he designed Bitcoin, and made the block generation either take more time, or have built-in interplanetary redundancy.
This won't happen as described. If bicoin is not replaced with something more latency-tolerant, the Mars Colony would start their own blockchain with their own version number. The reason a split of the existing chain would not be attempted is that the longest blockchain wins. That implies the Mars fork would never be accepted.
Of course, exchanges supporting latency-tolerant transactions would be set up. A bigger problem, is what prevents the larger network from manipulating the smaller one?
