NASA Astronauts and STS-133 mission crew members, from left, Mission Specialists Nicole Stott, Michael Barratt, Pilot Eric Boe, Commander Steve Lindsey, Mission Specialists Alvin Drew, and Steve Bowen pose for a photograph in front of the space shuttle Discovery after they landed, Wednesday, March 9, 2011, at Kennedy Space Center in Cape Canaveral, Fla., completing Discovery's 39th and final flight. Since 1984, Discovery flew 39 missions, spent 365 days in space, orbited Earth 5,830 times and traveled 148,221,675 miles. Photo credit: (NASA/Bill Ingalls)