Space travel in the future will not always be done on space craft. Trips to distant places will sometimes be accomplished by beaming people there. It takes days to fly to the moon, but you'll one day be able to beam someone there in three seconds. Beyond this century, this will be the prevalent form of space travel. It has all kinds of advantages over other methods of space travel. In the coming century, humans will walk on Mars and eventually discover shocking anthropological evidence that intelligent life has existed there.