4 of 36: The crew of space shuttle Endeavour, clockwise from left, British born U.S. astronaut, pilot Greg Johnson, European Space Agency astronaut Roberto Vittori, of Italy, Canadian born U.S. astronaut Greg Chamitoff, mission specialist Drew Feustel, mission specialist Mike Fincke and commander Mark Kelly, leave the Operations and Checkout building on their way to Pad 39A to board the shuttle at the Kennedy Space Center Visitors Center in Cape Canaveral, Fla., Monday, May 16, 2011.(AP Photo/John Raoux) (AP Photo/ John Raoux)

Share this gallery