What is the future of space travel? People like German astronaut Thomas Reiter are certain that in the coming decades, it will be possible to take short tourist trips to the edge of space to experience weightlessness. At the moment, the cost of such a trip is astronomical, but by mid-century, they are expected to become affordable for many. In two, or perhaps three decades, some say the first bases will be set up on the moon. But proponents of these plans say that will only be possible if the major space-traveling countries join forces. Scientists already know there are enough natural resources present on the moon to support a base there. Yet Reiter estimates that it will take at least three decades until the first human sets foot on Mars.