While we humans are still pretty much stuck on this big rotating rock we call the Earth – with the exception of a few lucky astronauts who reside on the International Space Station – Elon Musk and his extremely busy SpaceX have been working around the clock to make extended space travel a reality. Of course, getting off this monstrous rock is only a small part of the equation. We need things like artificial gravity, advanced life support systems, protection from the insane radiation that clouds the cosmos, and the list goes on. But, SpaceX has taken us one step closer with its Falcon 9 rocket, which was used to prove that rockets are reusable when it launched the SES10 Satellite into orbit back in April of this year. The problem with the Falcon 9 rocket, however, is that it’s somewhat limited as far as payload. It will be used to launch NASA’s X-37B into space, but we’ll still need something more powerful and reusable to be able to become a truly spacefaring species.