SpaceX Polaris Dawn crew lands at launch site ahead of 1st-ever private spacewalk mission (photos, video) Space.comSpaceX is about to send four people on a wild — and risky — mission into the radiation belts. Here’s what to know CNNPolaris Dawn astronauts, set to perform first commercial spacewalk, arrive in Florida ahead of launch Spaceflight NowPolaris Dawn private astronaut mission ready for launch SpaceNews