The next frontier for the ultimate globetrotter? Space. Once you’ve crisscrossed the seven continents, there’s only one place left to go: up.

Thanks to a group of innovative companies developing new space vehicles, the approaching wind down of NASA’s shuttle program and a Russian space program that welcomes civilian travelers, space tourism is poised to become the next extreme travel niche.

So what trips can be booked now, and what’s likely to remain a sci-fi fantasy? Our new guide, How to Travel in Space, covers all the latest developments in this fledgling industry, from Virgin Galactic’s recent advances to gravity-free treks from space travel agent Space Adventures. Check out the key space travel companies to watch, learn about what it takes to go into orbit and find out just how much lifting off for a weightless vacation will cost you so, well, you can start saving. Nothing makes private jet travel look more affordable than heading into the great beyond.