Everything you need to know about SpaceX's big moon announcement

Elon Musk is nothing if not ambitious.  The SpaceX founder wants his company to lead the charge to build a city on Mars, and next year, the spaceflight company plans to fly its first astronauts to the International Space Station for NASA. SEE ALSO: SpaceX wants to send 2 people around the moon in 2018So generally, SpaceX is pretty busy. But that doesn't mean it can't take on just one other little project, right? Namely, in 2018, SpaceX plans to fly a pair of (presumably rich) private c