The STS-135 mission specialist Rex Walheim, left, Doug Hurley, pilot; second from left, Sandy Magnus, mission specialist; and Chris Ferguson, commander, right, stop and take a moment to look up at the space shuttle Atlantis prior to boarding at launch pad 39A, Friday, July 8, 2011 at the NASA Kennedy Space Center in Cape Canaveral, Fla. The launch of Atlantis, STS-135, is the final flight of the shuttle program, a 12-day mission to the International Space Station. Photo Credit: (NASA/Jerry Ross)