The so-called “space billionaires”—Jeff Bezos, Richard Branson and Elon Musk — imagine a day when people will live and work in space, gradually transforming humanity into a multi-planet species. The next step in that direction is the development of a space tourism industry, and that’s about to become a reality. The rich will go first, of course, paying hundreds of thousands of dollars to be astronauts — if only for a few minutes. These extreme-tourism-style flights by Blue Origin, Virgin Galactic and SpaceX are seen as a precursor to an era when blasting to and from space will be considered