JSC2011-E-040202 (2 March 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, departs from the Moffett Field (Calif.) flight operations center for his trip home to Houston after he and his crew trained in the Vertical Motion Simulator (VMS) at NASA's Ames Research Center in Mountain View, March 2, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040324 (30 March 2011) --- NASA astronaut Doug Hurley, STS-135 pilot, waits in a pressure chamber before a test of his Russian Sokol spacesuit at the Zvezda facility in Moscow on March 30, 2011. The crew of the final shuttle mission traveled to Moscow for a suit fit check of their Russian Sokol suits which would be required in the event of an emergency. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040220 (10 March 2011) --- NASA astronaut Rex Walheim (left), STS-135 mission specialist, and astronaut Mike Fossum are aided by divers as they work in a mock-up of the space shuttle's payload bay as the crew of STS-135 trains for a spacewalk in the Neutral Buoyancy Laboratory near NASA?s Johnson Space Center on March 10, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040217 (10 March 2011) --- NASA astronaut Rex Walheim, STS-135 mission specialist, is aided by divers as he works with astronaut Mike Fossum in a mock-up of the space shuttle's payload bay as the crew of STS-135 trains for a spacewalk in the Neutral Buoyancy Laboratory near NASA?s Johnson Space Center on March 10, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059419 (17 May 2011) --- Photographers take pictures of the STS-135 crew as the space shuttle Atlantis is moved from the Orbiter Processing Facility to the Vehicle Assembly Building at NASA?s Kennedy Space Center on May 17, 2011. The move, known as rollover, is a milestone in the preparation for launch as the orbiter leaves its processing hangar to be prepped for its final flight. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040358 (7 April 2011) --- NASA astronaut Doug Hurley, STS-135 pilot, exits the hatch of the space shuttle Atlantis during the STS-135 Crew Equipment Interface Test (CEIT) in the Orbiter Processing Facility at NASA?s Kennedy Space Center, Florida on April 7, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059470 (31 May 2011) --- NASA astronaut Doug Hurley, STS-135 pilot, is seen in a partial silhouette against the space shuttle Atlantis as the spacecraft for the program's final mission moves to Launch Pad 39A during rollout at NASA?s Kennedy Space Center in Florida May 31, 2011. Photo credit: NASA photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059418 (17 May 2011) --- The crew of STS-135, from right, Sandy Magnus, Doug Hurley, Chris Ferguson and Rex Walheim pose for a group photo as the space shuttle Atlantis (out of frame) is moved from the Orbiter Processing facility to the Vehicle Assembly Building at NASA?s Kennedy Space Center in Florida on May 17, 2011. The move, known as rollover, is a milestone in the preparation for launch as the orbiter leaves its processing hangar to be prepped for its final flight. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059632 (21 June 2011) --- NASA astronaut Sandy Magnus, STS-135 mission specialist, participates in safety training in the M113 personnel carrier during the Terminal Countdown Demonstration Test (TCDT) at NASA?s Kennedy Space Center on June 21, 2011. TCDT serves as the prelaunch countdown rehearsal for the final space shuttle mission, which is scheduled for launch on July 8. The M113 would be used in the event of an emergency at the pad forcing the crew to evacuate. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-067680 (12 July 2011) --- This is an overall view of the wiring for the simulated shuttle payload bay in the Shuttle Avionics Integration Laboratory (SAIL) at the Johnson Space Center in Houston on July 12, 2011. The laboratory is a skeletal avionics version of the shuttle that uses actual orbiter hardware and flight software. The facility even carries the official orbiter designation as Orbiter Vehicle 095. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-060127 (28 June 2011) --- The STS-135 crew practices rendezvous and docking with the International Space Station in the Systems Engineering Simulator at NASA?s Johnson Space Center in Houston June 28, 2011. NASA astronaut Chris Ferguson, commander, is at back left, and astronaut Rex Walheim, mission specialist, is at back right; and astronaut Doug Hurley, pilot, is at center. The session marked the crew's final scheduled training in the "Dome" in preparation for the final mission of the Space Shuttle Program. Photo credit: NASA photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059375 (4 May 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, plays the drums with the all-astronaut band known as Max Q as the group performs on Innovation Day at NASA?s Johnson Space Center in Houston May 4, 2011. Vocalist Tracy Caldwell Dyson is at left. Guitarist Drew Feustel is at right. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040281 (24 March 2011) --- NASA astronaut Sandy Magnus, STS-135 mission specialist, works on the middeck of the Full-Fuselage Trainer during a post-insertion training session in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center on March 24, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-068012 (21 July 2011) --- Milt Heflin, associate director (technical) of the Johnson Space Center, stands under the wing of the space shuttle Atlantis after it landed on July 21, 2011 at the Kennedy Space Center in Florida. The landing completed STS-135, the final mission of the NASA Space Shuttle Program. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040298 (28 March 2011) --- NASA astronaut Rex Walheim, STS-135 mission specialist, undergoes a fit check of his Sokol spacesuit at the Zvezda facility in Moscow on March 28, 2011. The crew of the final shuttle mission traveled to Moscow for a suit fit check of their Russian suits would be required in the event of an emergency. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040265 (23 March 2011) --- A long parade of media is escorted between buildings at NASA?s Johnson Space Center in Houston for a media availability with the crew of STS-135 in the Systems Engineering Simulator March 23, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040372 (8 April 2011) --- Technicians inspect the payload bay of the space shuttle Atlantis during the STS-135 Crew Equipment Interface Test (CEIT) in the Orbiter Processing Facility at NASA?s Kennedy Space Center, Florida on April 8, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040330 (30 March 2011) --- NASA astronaut Chris Ferguson (foreground), STS-135 commander, visits Red Square in Moscow on March 30, 2011. The crew of the final shuttle mission traveled to Moscow for a suit fit check of their Russian Sokol suits which would be required in the event of an emergency. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040357 (7 April 2011) --- NASA astronauts Chris Ferguson (right), STS-135 commander; and Doug Hurley, pilot, pose for a photo on the cockpit of the space shuttle Atlantis during the STS-135 Crew Equipment Interface Test (CEIT) in the Orbiter Processing Facility at NASA?s Kennedy Space Center, Florida on April 7, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-068008 (21 July 2011) --- Red paint marks the location where Atlantis' main landing gear came to a stop on the runway after the space shuttle landed at the Kennedy Space Center in Florida on July 21, 2011. The landing completed STS-135, the final mission of the NASA Space Shuttle Program. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059488 (31 May 2011) --- The space shuttle Atlantis moves away from the Vehicle Assembly Building on its way to Launch Pad 39A during rollout at NASA?s Kennedy Space Center in Florida on May 31, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-068007 (21 July 2011) --- Green paint marks the location where Atlantis' nose landing gear came to a stop on the runway after the space shuttle landed at the Kennedy Space Center in Florida on July 21, 2011. The landing completed STS-135, the final mission of the NASA Space Shuttle Program. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-067589 (8 July 2011) --- The space shuttle Atlantis launches for the STS-135 mission to the International Space Station in the final mission of the Space Shuttle Program at NASA?s Kennedy Space Center in Florida. Liftoff was at 11:29 a.m. (EDT) on July 8, 2011. Onboard are NASA astronauts Chris Ferguson, STS-135 commander; Doug Hurley, pilot; Sandy Magnus and Rex Walheim, both mission specialists. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040335 (4 April 2011) --- NASA astronauts Rex Walheim, right, Sandy Magnus, foreground, both mission specialists, and Doug Hurley, pilot, work on the flight deck as the crew of STS-135 trains in the Fixed Base Simulator at NASA?s Johnson Space Center in Houston April 4, 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

JSC2011-E-040200 (2 March 2011) --- The landing approach to the Kennedy Space Center is seen in a heads up display as the STS-135 crew trains 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-040322 (29 March 2011) --- NASA astronaut Sandy Magnus, STS-135 mission specialist, undergoes a fit check of her Sokol spacesuit March 29, 2011, at the Zvezda facility in Moscow. The crew of the final shuttle mission traveled to Moscow for a suit fit check of their Russian Soyuz suits that will be required in the event of an emergency. Photo credit: NASA Photo / Houston Chronicle, Smiley N. Pool

JSC2011-E-040209 (10 March 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, takes a photo of himself with astronaut Mike Fossum before the crew of the final shuttle mission trains March 10, 2011 in the Neutral Buoyancy Laboratory near the Johnson Space Center in Houston. Fossum will fly to the International Space Station aboard a Russian Soyuz spacecraft scheduled for launch in May and will serve as flight engineer for Expedition 28 and as commander for Expedition 29. Since the crew of the final shuttle mission will consist of only four astronauts, the ISS crew will perform the mission's single scheduled spacewalk, and the crew of STS-135 will function in support of the EVA, with Rex Walheim serving as the internally-based 'quarterback' for the spacewalk. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040366 (8 April 2011) --- Close-up photo of tools taken during the STS-135 crew members' inspection of the equipment they will use in space. The inspection was part of the STS-135 Crew Equipment Interface Test (CEIT) conducted April 8, 2011 at NASA?s Kennedy Space Center in Florida. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

NASA astronaut Rex Walheim is lowered into the water to train for spacewalk in the Neutral Buoyancy Laboratory (NBL) on Tuesday, March 22, 2011, in Houston. ( NASA Photo / Houston Chronicle, Smiley N. Pool )

JSC2011-E-059636 (21 June 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, participates in safety training in the M113 personnel carrier during the Terminal Countdown Demonstration Test (TCDT) at NASA?s Kennedy Space Center on June 21, 2011. TCDT serves as the prelaunch countdown rehearsal for the final space shuttle mission, which is scheduled for launch on July 8. The M113 would be used in the event of an emergency at the pad forcing the crew to evacuate. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040205 (2 March 2011) --- A NASA T-38 jet trainer piloted by astronaut Chris Ferguson, STS-135 commander, takes off from Moffett Field in California for a flight home to Houston after Ferguson and his crew trained in the Vertical Motion Simulator (VMS) at NASA's Ames Research Center in Mountain View, March 2, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

The space shuttle Atlantis moves to Launch Pad 39A during rollout at the Kennedy Space Center on Tuesday, May 31, 2011, in Florida. ( NASA Photo / Houston Chronicle, Smiley N. Pool ).

JSC2011-E-067687 (21 July 2011) --- The drag chute is deployed as the space shuttle Atlantis lands on July 21 at the Kennedy Space Center in Florida. The landing completed STS-135, the final mission of the NASA Space Shuttle Program. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-205603 (2 Nov. 2011) --- The current and former astronauts who formed the crews of STS-1, the first space shuttle mission, and STS-135, the final shuttle mission, pose for a group photo at the Johnson Space Center in Houston on Nov. 2, 2011. They are, from left, John Young, STS-1 commander, Robert Crippen, STS-1 pilot, with the STS-135 crew of commander Chris Ferguson, pilot Doug Hurley and mission specialists Sandy Magnus and Rex Walheim. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

The space shuttle Atlantis moves to Launch Pad 39A during rollout at the Kennedy Space Center on Tuesday, May 31, 2011, in Florida. ( NASA Photo / Houston Chronicle, Smiley N. Pool ).

JSC2011-E-040193 (2 March 2011) --- NASA astronaut Chris Ferguson (left), STS-135 commander, confers with astronaut Rex Walheim, mission specialist, as the Atlantis crew participates in a briefing before a training session in the Vertical Motion Simulator (VMS) at NASA's Ames Research Center in Mountain View, Calif. March 2, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-067587 (8 July 2011) --- The space shuttle Atlantis launches for the STS-135 mission to the International Space Station in the final mission of the Space Shuttle Program at NASA?s Kennedy Space Center in Florida. Liftoff was at 11:29 a.m. (EDT) on July 8, 2011. Onboard are NASA astronauts Chris Ferguson, STS-135 commander; Doug Hurley, pilot; Sandy Magnus and Rex Walheim, both mission specialists. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-067611 (8 July 2011) --- The space shuttle Atlantis launches for the STS-135 mission to the International Space Station in the final mission of the Space Shuttle Program at NASA?s Kennedy Space Center in Florida. Liftoff was at 11:29 a.m. (EDT) on July 8, 2011. Onboard are NASA astronauts Chris Ferguson, STS-135 commander; Doug Hurley, pilot; Sandy Magnus and Rex Walheim, both mission specialists. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-067613 (8 July 2011) --- The space shuttle Atlantis launches for the STS-135 mission to the International Space Station in the final mission of the Space Shuttle Program at NASA?s Kennedy Space Center in Florida. Liftoff was at 11:29 a.m. (EDT) on July 8, 2011. Onboard are NASA astronauts Chris Ferguson, STS-135 commander; Doug Hurley, pilot; Sandy Magnus and Rex Walheim, both mission specialists. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040270 (24 March 2011) --- NASA astronaut Chris Ferguson, left, STS-135 commander, dons his training version of a shuttle launch and entry suit before participating in a post-insertion training session with NASA astronauts Doug Hurley, pilot, and Sandy Magnus, mission specialist, March 24, 2011, in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center in Houston. Hurley and Magnus are wearing their liquid-cooled undergarments for the orange suit. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-067645 (8 July 2011) --- The space shuttle Atlantis launches for the STS-135 mission to the International Space Station in the final mission of the Space Shuttle Program at NASA?s Kennedy Space Center in Florida. Liftoff was at 11:29 a.m. (EDT) on July 8, 2011. Onboard are NASA astronauts Chris Ferguson, STS-135 commander; Doug Hurley, pilot; Sandy Magnus and Rex Walheim, both mission specialists. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

NASA astronaut Chris Ferguson undergoes a fit check of his Sokol space suit at the Zvezda facility on Tuesday, March 29, 2011, in Moscow. The crew of the final shuttle mission traveled to Moscow for a suit fit check of their Russian Soyuz suits that will be required in the event of an emergency. ( NASA Photo / Houston Chronicle, Smiley N. Pool )

JSC2011-E-040343 (7 April 2011) --- NASA astronaut Doug Hurley, STS-135 pilot, looks at the thermal protection system on the underside of the space shuttle Atlantis during the mission's Crew Equipment Interface Test (CEIT) at the Kennedy Space Center in Florida on April 7, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040272 (24 March 2011) --- Suit technicians assist the crew of STS-135 in donning their training versions of a shuttle launch and entry suit before they participate in a post-insertion training session in the Full-Fuselage Trainer in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center in Houston March 24, 2011. From left are NASA astronauts Doug Hurley, pilot, along with Sandy Magnus and Rex Walheim, both mission specialists. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059397 (13 May 2011) --- NASA astronaut Rex Walheim, STS-135 mission specialist, simulates a spacewalk in the Virtual Reality Laboratory at NASA?s Johnson Space Center May 13, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-060140 (29 June 2011) --- NASA astronaut Rex Walheim laughs with his crewmates as STS-135 commander Chris Ferguson gets a refresher on the use of the waste management system on the International Space Station as the crew trains at NASA?s Johnson Space Center June 29, 2011. The day's training marked the crew's final scheduled sessions in the Space Vehicle Mock-up Facility at JSC. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-067641 (8 July 2011) --- The space shuttle Atlantis launches for the STS-135 mission to the International Space Station in the final mission of the Space Shuttle Program at NASA?s Kennedy Space Center in Florida. Liftoff was at 11:29 a.m. (EDT) on July 8, 2011. Onboard are NASA astronauts Chris Ferguson, STS-135 commander; Doug Hurley, pilot; Sandy Magnus and Rex Walheim, both mission specialists. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059628 (21 June 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, laughs with his crew members before safety training in the M113 personnel carrier during the Terminal Countdown Demonstration Test (TCDT) at NASA?s Kennedy Space Center on June 21, 2011. TCDT serves as the prelaunch countdown rehearsal for the final space shuttle mission, which is scheduled for launch on July 8. The M113 would be used in the event of an emergency at the pad forcing the crew to evacuate. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059411 (17 May 2011) --- NASA astronaut Rex Walheim, STS-135 mission specialist, watches as the space shuttle Atlantis is moved May 17, 2011. The move, known as rollover, is a milestone in the preparation for launch as the orbiter leaves its processing hangar to be prepped for its final flight. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040345 (7 April 2011) --- NASA astronauts Rex Walheim and Sandy Magnus, STS-135 mission specialists, inspect the front landing gear of the space shuttle Atlantis during the STS-135 Crew Equipment Interface Test (CEIT) at NASA?s Kennedy Space Center, Florida on April 7, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-060800 (30 June 2011) --- The STS-135 crew meets with the Johnson Space Center public affairs team before the crew's media briefing at NASA?s Johnson Space Center in Houston on June 30, 2011. The press conference provided the last scheduled opportunity for a large group of press to speak with the crew before the final launch on July 8. Shown, from left, are Rob Navias and James Hartsfield of public affairs, and NASA astronauts Sandy Magnus, Rex Walheim, Chris Ferguson and Doug Hurley. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040323 (29 March 2011) --- NASA astronaut Sandy Magnus, STS-135 mission specialist, looks at a snow-covered neighborhood out the window of a van carrying her back to Star City following a fit check of her Sokol spacesuit at the Zvezda facility in Moscow March 29, 2011. The crew of the final shuttle mission traveled to Moscow for a suit fit check of their Russian spacesuits which would be required in the event of an emergency. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-067590 (8 July 2011) --- The space shuttle Atlantis launches for the STS-135 mission to the International Space Station in the final mission of the Space Shuttle Program at NASA?s Kennedy Space Center in Florida. Liftoff was at 11:29 a.m. (EDT) on July 8, 2011. Onboard are NASA astronauts Chris Ferguson, STS-135 commander; Doug Hurley, pilot; Sandy Magnus and Rex Walheim, both mission specialists. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-068761 (22 July 2011) --- A small portion of a large Ellington Field crowd is seen on July 22, 2011 through a door bearing a STS-135 sticker on its window. A short while later the crew of the space shuttle Atlantis' mission used this door for its entrance during a welcome home ceremony. STS-135 is the final mission of the NASA Space Shuttle Program. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-067975 (21 July 2011) --- The sun rises over the space shuttle Atlantis after landing July 21 at the Kennedy Space Center in Florida. The landing completed STS-135, the final mission of the NASA Space Shuttle Program. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

NASA astronaut Sandy Magnus waves as she is lowered into the water to train for spacewalk in the Neutral Buoyancy Laboratory (NBL) on Tuesday, March 22, 2011, in Houston. ( NASA Photo / Houston Chronicle, Smiley N. Pool )

JSC2011-E-040332 (30 March 2011) --- NASA astronauts Rex Walheim and Chris Ferguson visit Red Square in Moscow on March 30, 2011. The crew of the final shuttle mission traveled to Moscow for a suit fit check of their Russian Soyuz suits which would be required in the event of an emergency. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

The crew of STS-135, from left, Doug Hurley, Chris Ferguson, Sandy Magnus and Rex Walheim walk between buildings at the Johnson Space Center after a simulation in the motion based simulator on Friday, May 6, 2011, in Houston. ( NASA Photo / Houston Chronicle, Smiley N. Pool ).

JSC2011-E-040338 (7 April 2011) --- NASA astronauts Sandy Magnus and Rex Walheim, both STS-135 mission specialists, work in the Multi-Purpose Logistics Module in the Space Station Processing Facility during the STS-135 Crew Equipment Interface Test (CEIT) at the Kennedy Space Center in Florida on April 7, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040346 (7 April 2011) --- NASA astronauts Chris Ferguson, STS-135 commander; and Doug Hurley, pilot, inspect the front landing gear of the space shuttle Atlantis during the STS-135 Crew Equipment Interface Test (CEIT) at NASA?s Kennedy Space Center, Florida on April 7, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040273 (24 March 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, is reflected in a mirror before participating in a post-insertion training session in the Full-Fuselage Trainer in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center in Houston March 24, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-060796 (30 June 2011) --- Reporter Mark Carreau of Aviation Week takes notes during the STS-135 crew media briefing at NASA?s Johnson Space Center on June 30, 2011. The press conference provided the last scheduled opportunity for a large group of press to speak with the crew before the final launch on July 8. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059482 (31 May 2011) --- A Shuttle Training Aircraft (STA) piloted by NASA astronaut Chris Ferguson, STS-135 commander, is seen against the late afternoon sun as the crew of the final space shuttle mission practices landings at NASA?s Kennedy Space Center in Florida May 31. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-205596 (2 Nov. 2011) --- The current and former astronauts who formed the crews of STS-1, the first space shuttle mission, and STS-135, the final shuttle mission, pose for a group photo at the Johnson Space Center in Houston on Nov. 2, 2011. They are, from left, John Young, STS-1 commander, Robert Crippen, STS-1 pilot, with the STS-135 crew of commander Chris Ferguson, pilot Doug Hurley and mission specialists Sandy Magnus and Rex Walheim. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-068015 (21 July 2011) --- A technician works to secure the space shuttle Atlantis following its landing at the Kennedy Space Center in Florida on July 21, 2011. The landing brought to completion STS-135, the final mission of the NASA Space Shuttle Program. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-060132 (29 June 2011) --- NASA astronaut Doug Hurley crawls out of the Crew Compartment Trainer (CCT-2) mock-up while Rex Walheim waits as the crew of STS-135 trains in the Space Vehicle Mock-up Facility (SVMF) at NASA?s Johnson Space Center June 29, 2011. The training marked the crew's final scheduled session in JSC's Shuttle Vehicle Mock-up Facility. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040219 (10 March 2011) --- NASA astronaut Rex Walheim (left), STS-135 mission specialist, and astronaut Mike Fossum are aided by divers as they work in a mock-up of the space shuttle's payload bay as the crew of STS-135 trains for a spacewalk in the Neutral Buoyancy Laboratory near NASA?s Johnson Space Center on March 10, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040290 (27 March 2011) --- Moscow stretches out in all directions as seen from a commercial flight carrying NASA astronauts Doug Hurley, STS-135 pilot, and Rex Walheim, mission specialist, to Moscow, Russia on March 27, 2011. The crew of the final shuttle mission traveled to Moscow to be fitted for Russian Sokol spacesuits which would be required in the event of an emergency. If the shuttle is unable to return to Earth, the crew will remain on the International Space Station and return on a staggered basis in the course of a year on scheduled Soyuz flights to the station. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-060797 (30 June 2011) --- Commander Chris Ferguson, pilot Doug Hurley, mission specialist Sandy Magnus and mission specialist Rex Walheim participate in the STS-135 crew media briefing at NASA?s Johnson Space Center June 30, 2011. The press conference provided the last scheduled opportunity for a large group of press to speak with the crew before the final launch on July 8. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-060793 (30 June 2011) --- The crew of STS-135, from left, pilot Doug Hurley, mission specialists Rex Walheim and Sandy Magnus, and commander Chris Ferguson pose for a group photo following the crew media briefing at the Johnson Space Center in Houston on June 30, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

as the space shuttle Atlantis moves to Launch Pad 39A at the Kennedy Space Center on Tuesday, May 31, 2011, in Florida. ( NASA Photo / Houston Chronicle, Smiley N. Pool ).

JSC2011-E-040221 (10 March 2011) --- NASA astronaut Mike Fossum is aided by divers as he trains for a spacewalk with astronaut Rex Walheim, STS-135 mission specialist, in the Neutral Buoyancy Laboratory near NASA?s Johnson Space Center on March 10, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-068004 (21 July 2011) --- KSC director Bob Cabana, center frame, congratulates members of the damage assessment team after the space shuttle Atlantis landed on July 21 at the Kennedy Space Center in Florida. The landing marked the completion of STS-135, the final mission of the NASA Space Shuttle Program. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059386 (11 May 2011) --- In this high-angle wide shot, STS-135 flight director Kwatsi Alibaruho, (center with back toward camera), and astronaut Steve Robinson (center, facing camera), CAPCOM, work in the Mission Control Center at NASA?s Johnson Space Center during a simulation exercise with the crew on May 11, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040373 (8 April 2011) --- Technicians inspect the payload bay of the space shuttle Atlantis during the STS-135 Crew Equipment Interface Test (CEIT) in the Orbiter Processing Facility at NASA?s Kennedy Space Center in Florida on April 8, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040299 (28 March 2011) --- NASA astronaut Rex Walheim, STS-135 mission specialist, undergoes a fit check of his Sokol suit at the Zvezda facility in Moscow on March 28, 2011. The crew of the final shuttle mission traveled to Moscow for a suit fit check of their Russian Sokol spacesuits which would be required in the event of an emergency. Walheim's name appears first in English and then in Russian on his suit. The order is reversed on the suits of Russian cosmonauts. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-067676 (12 July 2011) --- A close-up view of controls and displays on the forward flight deck of OV-095 in the Shuttle Avionics Integration Laboratory (SAIL) at the Johnson Space Center in Houston, July 12, 2011. The laboratory is a skeletal avionics version of the shuttle that uses actual orbiter hardware and flight software. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-068773 (22 July 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, listens as a crewmate addresses the crowd during a July 22 welcome home ceremony for the crew of the space shuttle Atlantis at Ellington Field in Houston. STS-135 is the final mission of the NASA Space Shuttle Program. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059490 (31 May 2011) --- The space shuttle Atlantis moves away from the Vehicle Assembly Building on its way to Launch Pad 39A during rollout at NASA?s Kennedy Space Center in Florida on May 31, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-060141 (29 June 2011) --- NASA astronauts Sandy Magnus and Chris Ferguson practice setup of an exercise ergometer as the crew of STS-135 trains in the Crew Compartment Trainer (CCT) mock-up at NASA?s Johnson Space Center in Houston June 29, 2011. The training marked the crew's final scheduled session in the Space Vehicle Mock-up Facility. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

NASA astronaut Sandy Magnus is helped out of her training EMU after training for spacewalk in the Neutral Buoyancy Laboratory (NBL) on Tuesday, March 22, 2011, in Houston. In the background, a test is performed on the Orion capsule. ( NASA Photo / Houston Chronicle, Smiley N. Pool )

NASA astronauts Rex Walheim, Doug Hurley and Chris Ferguson work on computers in an exercises to overcome a power loss on the International Space Station as the crew of STS-135, the final space shuttle mission, trains in the Space Station Training Facility at the Johnson Space Center on Thursday, May 19, 2011, in Houston. ( NASA Photo / Houston Chronicle, Smiley N. Pool ).

JSC2011-E-059494 (31 May 2011) --- The space shuttle Atlantis is seen on Launch Pad 39A at NASA?s Kennedy Space Center on May 31, 2011, in Florida. The orbiter is scheduled to fly the final mission of the Space Shuttle Program, launching on July 8. Photo credit: NASA Photo / Houston Chronicle, Smiley N. Pool

JSC2011-E-205608 (2 Nov. 2011) --- The current and former astronauts who formed the crews of STS-1, the first space shuttle mission, and STS-135, the final shuttle mission, pose for a group photo in a training facility at the Johnson Space Center in Houston on Nov. 2, 2011. They are, from left, Doug Hurley, STS-135 pilot, Robert Crippen, STS-1 pilot, John Young, STS-1 commander, with STS-135 commander Chris Ferguson, and mission specialists Sandy Magnus and Rex Walheim. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059424 (19 May 2011) --- The crew of STS-135, the final space shuttle mission, trains in the Space Station Training Facility at NASA?s Johnson Space Center May 19, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-060138 (29 June 2011) --- NASA astronaut Chris Ferguson crawls out of the Crew Compartment Trainer (CCT-2) as the crew of STS-135 trains at NASA?s Johnson Space Center June 29, 2011. The training marked the crew's final scheduled session in the Space Vehicle Mock-up Facility. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-067976 (21 July 2011) --- The sun rises over the space shuttle Atlantis after landing July 21 at the Kennedy Space Center in Florida. The landing completed STS-135, the final mission of the NASA Space Shuttle Program. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059491 (31 May 2011) --- The space shuttle Atlantis moves to Launch Pad 39A during rollout at NASA?s Kennedy Space Center in Florida on May 31, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059495 (31 May 2011) --- Thermal protection tiles are seen on the underside of the space shuttle Atlantis on Launch Pad 39A at NASA?s Kennedy Space Center in Florida May 31, 2011. The orbiter is scheduled to fly the final mission of the Space Shuttle Program, launching on July 8. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

NASA astronaut Chris Ferguson undergoes a fit check of his Sokol space suit at the Zvezda facility on Tuesday, March 29, 2011, in Moscow. The crew of the final shuttle mission traveled to Moscow for a suit fit check of their Russian Soyuz suits that will be required in the event of an emergency. ( NASA Photo / Houston Chronicle, Smiley N. Pool )

JSC2011-E-067588 (8 July 2011) --- The space shuttle Atlantis launches for the STS-135 mission to the International Space Station in the final mission of the Space Shuttle Program at NASA?s Kennedy Space Center in Florida. Liftoff was at 11:29 a.m. (EDT) on July 8, 2011. Onboard are NASA astronauts Chris Ferguson, STS-135 commander; Doug Hurley, pilot; Sandy Magnus and Rex Walheim, both mission specialists. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040348 (7 April 2011) --- A technician uses binoculars to look over the space shuttle Atlantis as the crew of STS-135 uses a basket/carrier to inspect Atlantis' payload bay during the STS-135 Crew Equipment Interface Test (CEIT) at NASA?s Kennedy Space Center, Florida on April 7, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-067612 (8 July 2011) --- The space shuttle Atlantis launches for the STS-135 mission to the International Space Station in the final mission of the Space Shuttle Program at NASA?s Kennedy Space Center in Florida. Liftoff was at 11:29 a.m. (EDT) on July 8, 2011. Onboard are NASA astronauts Chris Ferguson, STS-135 commander; Doug Hurley, pilot; Sandy Magnus and Rex Walheim, both mission specialists. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059446 (31 May 2011) --- The crew of the space shuttle Atlantis, from left, commander Chris Ferguson, pilot Doug Hurley and mission specialists Sandy Magnus and Rex Walheim address a news conference as the shuttle moves to Launch Pad 39A during rollout at NASA?s Kennedy Space Center in Florida on May 31, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040269 (24 March 2011) --- The crew members of STS-135 are briefed by trainers before they participate in a post-insertion training session in the Full-Fuselage Trainer in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center in Houston March 24, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059493 (31 May 2011) --- The space shuttle Atlantis is seen in the background on Launch Pad 39A at NASA?s Kennedy Space Center in Florida on May 31, 2011. The crawler/transporter is seen slowly driving away from the launch pad after making its final scheduled delivery of a shuttle. The orbiter is scheduled to fly the final mission of the Space Shuttle Program, launching on July 8. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-060128 (29 June 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, left, looks out over the Space Vehicle Mock-up Facility (SVMF) after the crew of the final shuttle mission trained in the facility at NASA?s Johnson Space Center in Houston on June 29, 2011. The training marked the crew's final scheduled session in the SVMF. NASA astronaut Sandy Magnus, mission specialist, is in background at center. Photo credit: NASA photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040195 (2 March 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, takes photos of the massive Vertical Motion Simulator (VMS) at NASA's AMES Research Center before the crew trains in the simulator on Wednesday, March 2, 2011, in Mountain View, Calif. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-059478 (31 May 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, is seen in silhouette against the Vehicle Assembly Building as the space shuttle Atlantis moves to Launch Pad 39A during rollout at NASA?s Kennedy Space Center in Florida May 31, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool