Charles Bolden, Bob Cabana, Pete Nickolenko

    NASA Administrator Charles Bolden, center, Bob Cabana, director of the Kennedy Space Center, left and launch director, Pete Nickolenko, share a light moment before Space Shuttle Atlantis lands at the Kennedy Space Center at Cape Canaveral, Fla. Thursday, July 21, 2011. The landing of Atlantis marks the end of NASA’s 30 year space shuttle program. (AP Photo/Scott Audette, Pool)