The STS-133 crew poses for a photo in front of Discovery on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center.

The STS-133 crew poses for a photo in front of space shuttle Discovery on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida. From left, are Mission Specialists Nicole Stott and Michael Barratt, Pilot Eric Boe, Commander Steve Lindsey, and Mission Specialists Alvin Drew and Steve Bowen. Discovery and crew returned to Earth at 11:57 a.m., completing a 13-day, 5.3-million-mile mission to the International Space Station.

STS-133 delivered the Permanent Multipurpose Module, packed with supplies and critical spare parts, as well as Robonaut 2, the dexterous humanoid astronaut helper, to the orbiting outpost. STS-133 was Discovery's 39th and final mission. This was the 133rd Space Shuttle Program mission and the 35th shuttle voyage to the space station. Photo credit: NASA/Kim Shiflett