CAPE CANAVERAL, Fla. -- The STS-135 astronauts prepare to depart NASA's Kennedy Space Center in Florida to return to NASA's Johnson Space Center in Houston. Space shuttle Atlantis and its crew touched down on Kennedy's Shuttle Landing Facility runway 5:57 a.m., July 21, 2011, bringing a close to 30 years of space shuttle missions. Here, STS-135 Commander Chris Ferguson and his son walk toward a Gulfstream III jet that will take them back home. STS-135 Mission Specialist Sandy Magnus follows close behind them, at left. Securing the space shuttle fleet's place in history, Atlantis marked the 26th nighttime landing of the Space Shuttle Program and the 78th landing at Kennedy. Atlantis and its crew delivered to the International Space Station the Raffaello multi-purpose logistics module packed with more than 9,400 pounds of spare parts, equipment and supplies that will sustain station operations for the next year. STS-135 was the 33rd and final flight for Atlantis and the final mission of the Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- The STS-135 astronauts prepare to depart NASA's Kennedy Space Center in Florida to return to NASA's Johnson Space Center in Houston. Space shuttle Atlantis and its crew touched down on Kennedy's Shuttle Landing Facility runway 5:57 a.m., July 21, 2011, bringing a close to 30 years of space shuttle missions. Here, STS-135 Mission Specialist Rex Walheim and his family stop for a photo before boarding a Gulfstream III jet that will take them back home. Securing the space shuttle fleet's place in history, Atlantis marked the 26th nighttime landing of the Space Shuttle Program and the 78th landing at Kennedy. Atlantis and its crew delivered to the International Space Station the Raffaello multi-purpose logistics module packed with more than 9,400 pounds of spare parts, equipment and supplies that will sustain station operations for the next year. STS-135 was the 33rd and final flight for Atlantis and the final mission of the Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- The STS-135 astronauts prepare to depart NASA's Kennedy Space Center in Florida to return to NASA's Johnson Space Center in Houston. Space shuttle Atlantis and its crew touched down on Kennedy's Shuttle Landing Facility runway 5:57 a.m., July 21, 2011, bringing a close to 30 years of space shuttle missions. Here, STS-135 Commander Chris Ferguson and his son walk toward a Gulfstream III jet that will take them back home. Securing the space shuttle fleet's place in history, Atlantis marked the 26th nighttime landing of the Space Shuttle Program and the 78th landing at Kennedy. Atlantis and its crew delivered to the International Space Station the Raffaello multi-purpose logistics module packed with more than 9,400 pounds of spare parts, equipment and supplies that will sustain station operations for the next year. STS-135 was the 33rd and final flight for Atlantis and the final mission of the Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- The STS-135 astronauts prepare to depart NASA's Kennedy Space Center in Florida to return to NASA's Johnson Space Center in Houston. Space shuttle Atlantis and its crew touched down on Kennedy's Shuttle Landing Facility runway 5:57 a.m., July 21, 2011, bringing a close to 30 years of space shuttle missions. Here, STS-135 Mission Specialist Sandy Magnus walks toward a Gulfstream III jet that will take her back home. Securing the space shuttle fleet's place in history, Atlantis marked the 26th nighttime landing of the Space Shuttle Program and the 78th landing at Kennedy. Atlantis and its crew delivered to the International Space Station the Raffaello multi-purpose logistics module packed with more than 9,400 pounds of spare parts, equipment and supplies that will sustain station operations for the next year. STS-135 was the 33rd and final flight for Atlantis and the final mission of the Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Kim Shiflett

JSC2011-E-040204 (2 March 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, prepares for departure from Moffett Field in a T-38 trainer home to Houston after the crew of STS-135 trained in the Vertical Motion Simulator (VMS) at NASA's Ames Research Center in Mountain View, Calif. on March 2, 2011, Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040243 (2 March 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, prepares for departure from Moffett Field as he flies a T-38 trainer home to Houston after the crew of STS-135 trained in the Vertical Motion Simulator (VMS) at NASA's Ames Research Center on March 2, 2011, in Mountain View, Calif. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

CAPE CANAVERAL, Fla. – At the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida, STS-135 Pilot Doug Hurley and Mission Specialist Sandra Magnus (in the red helmet) prepare for departure in a T-38 training jet. The astronauts, along with Commander Chris Ferguson, were at the center for the traditional post-flight crew return presentation. To the left of the jet is the space shuttle's mate-demate device. STS-135 Mission Specialist Rex Walheim was unable to attend the Kennedy event. In July 2011, Atlantis and its crew delivered to the International Space Station the Raffaello multi-purpose logistics module packed with more than 9,400 pounds of spare parts, equipment and supplies that will sustain station operations for the next year. STS-135 was the 33rd and final flight for Atlantis and the final mission of the Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. – At the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida, STS-135 Pilot Doug Hurley and Mission Specialist Sandra Magnus (in the red helmet) prepare for departure in a T-38 training jet. The astronauts, along with Commander Chris Ferguson, were at the center for the traditional post-flight crew return presentation. STS-135 Mission Specialist Rex Walheim was unable to attend the Kennedy event. In July 2011, Atlantis and its crew delivered to the International Space Station the Raffaello multi-purpose logistics module packed with more than 9,400 pounds of spare parts, equipment and supplies that will sustain station operations for the next year. STS-135 was the 33rd and final flight for Atlantis and the final mission of the Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. – At the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida, STS-135 Pilot Doug Hurley and Mission Specialist Sandra Magnus (in the red helmet) prepare for departure in a T-38 training jet. The astronauts, along with Commander Chris Ferguson, were at the center for the traditional post-flight crew return presentation. STS-135 Mission Specialist Rex Walheim was unable to attend the Kennedy event. In July 2011, Atlantis and its crew delivered to the International Space Station the Raffaello multi-purpose logistics module packed with more than 9,400 pounds of spare parts, equipment and supplies that will sustain station operations for the next year. STS-135 was the 33rd and final flight for Atlantis and the final mission of the Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. – At the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida, STS-135 Mission Specialist Sandra Magnus prepares for departure in a T-38 training jet. Magnus, along with Commander Chris Ferguson and Pilot Doug Hurley, was at the center for the traditional post-flight crew return presentation. STS-135 Mission Specialist Rex Walheim was unable to attend the Kennedy event. In July 2011, Atlantis and its crew delivered to the International Space Station the Raffaello multi-purpose logistics module packed with more than 9,400 pounds of spare parts, equipment and supplies that will sustain station operations for the next year. STS-135 was the 33rd and final flight for Atlantis and the final mission of the Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. – At the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida, STS-135 Pilot Doug Hurley and Mission Specialist Sandra Magnus (in the red helmet) prepare for departure in a T-38 training jet. The astronauts, along with Commander Chris Ferguson, were at the center for the traditional post-flight crew return presentation. STS-135 Mission Specialist Rex Walheim was unable to attend the Kennedy event. In July 2011, Atlantis and its crew delivered to the International Space Station the Raffaello multi-purpose logistics module packed with more than 9,400 pounds of spare parts, equipment and supplies that will sustain station operations for the next year. STS-135 was the 33rd and final flight for Atlantis and the final mission of the Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Jim Grossmann