NASA Administrator Charles Bolden looks at the Space Shuttle Endeavour (STS-134) from the air traffic control tower at the Shuttle Landing Facility (SLF) shortly after Endeavour made its final landing at the Kennedy Space Center, Wednesday, June 1, 2011, in Cape Canaveral, Fla. Endeavour, after completing a 16-day mission to outfit the International Space Station, spent 299 days in space and traveled more than 122.8 million miles during its 25 flights. It launched on its first mission on May 7, 1992. Photo Credit: (NASA/Bill Ingalls)

The STS-134 astronauts from left, European Space Agency's Roberto Vittori, Gregory H. Johnson, pilot; Mark Kelly, commander; Michael Fincke, Greg Chamitoff, and Andrew Feustel all mission specialists, pose for a group photograph shortly after landing onboard the space shuttle Endeavour at the Shuttle Landing Facility (SLF) at Kennedy Space Center, Wednesday, June 1, 2011, in Cape Canaveral, Fla. Endeavour, completing a 16-day mission to outfit the International Space Station, spent 299 days in space and traveled more than 122.8 million miles during its 25 flights. It launched on its first mission on May 7, 1992. Photo Credit: (NASA/Bill Ingalls)

CAPE CANAVERAL, Fla. -- In the early morning hours after landing, space shuttle Endeavour's "towback" vehicle slowly pulls it from the Shuttle Landing Facility to Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. -- In the early morning hours after landing, space shuttle Endeavour's "towback" vehicle slowly pulls it from the Shuttle Landing Facility to Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. -- In the early morning hours after landing, space shuttle Endeavour's "towback" vehicle slowly pulls it from the Shuttle Landing Facility to Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. -- In the early morning hours after landing, space shuttle Endeavour's "towback" vehicle slowly pulls it from the Shuttle Landing Facility to Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. -- In the early morning hours after landing, space shuttle Endeavour's "towback" vehicle slowly pulls it from the Shuttle Landing Facility to Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. -- In the early morning hours after landing, space shuttle Endeavour's "towback" vehicle slowly pulls it from the Shuttle Landing Facility to Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. In the background is the massive Vehicle Assembly Building. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. -- A "towback" vehicle slowly pulls shuttle Endeavour from the Shuttle Landing Facility to Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. In the background is the massive Vehicle Assembly Building. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. -- A "towback" vehicle slowly pulls shuttle Endeavour from the Shuttle Landing Facility to Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. -- Workers accompany shuttle Endeavour as a "towback" vehicle slowly pulls it from the Shuttle Landing Facility to Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. -- A "towback" vehicle slowly pulls shuttle Endeavour from the Shuttle Landing Facility to Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. In the background is the massive Vehicle Assembly Building. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. -- In the early morning hours after landing, media photograph space shuttle Endeavour as a "towback" vehicle slowly pulls it from the Shuttle Landing Facility to Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

JSC2011-E-050159 (1 June 2011) --- An overall view of the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center photographed during STS-134/ULF-6 landing day activities. Photo credit: NASA

JSC2011-E-050134 (1 June 2011) --- An overall view of the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center photographed during STS-134/ULF-6 landing day activities. Photo credit: NASA

CAPE CANAVERAL, Fla. -- A "towback" vehicle slowly pulls shuttle Endeavour into Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. -- Workers accompany shuttle Endeavour as a "towback" vehicle slowly pulls it into Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. -- A "towback" vehicle slowly pulls shuttle Endeavour into Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida. A purge unit that pumps conditioned air into a shuttle after landing is connected to Endeavour's aft end. Once inside the processing facility, Endeavour will be prepared for future public display. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Endeavour and its crew delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Jack Pfaller

JSC2011-E-050168 (1 June 2011) --- An overall view of the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center photographed during STS-134/ULF-6 landing day activities. Flight directors Richard Jones (left) and Tony Ceccacci are visible in the foreground. Photo credit: NASA

JSC2011-E-050144 (1 June 2011) --- Astronauts Terry Virts (left) and Barry Wilmore, both STS-134 spacecraft communicators (CAPCOM), are pictured at their console in the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center during landing activities several hundred miles away at Kennedy Space Center, Florida. Photo credit: NASA

JSC2011-E-050145 (1 June 2011) --- Astronauts Terry Virts (foreground) and Barry Wilmore, both STS-134 spacecraft communicators (CAPCOM), are pictured at their console in the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center during landing activities several hundred miles away at Kennedy Space Center, Florida. Photo credit: NASA

STS134-S-078 (1 June 2011) --- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 24th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-079 (1 June 2011) --- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 24th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-077 (1 June 2011) --- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 24th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-115 (1 June 2011) --- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 24th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-114 (1 June 2011) --- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 24th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-109 (1 June 2011) --- Streams of smoke trail from the main landing gear tires as space shuttle Endeavour touches down on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida for the final time marking the 24th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-089 (1 June 2011) --- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 24th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-113 (1 June 2011) --- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 24th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-068 (1 June 2011) --- Space shuttle Endeavour lands on Runway 15 on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida for the final time. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-110 (1 June 2011) --- Space shuttle Endeavour approaches Runway 15 on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida for the final time marking the 24th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-080 (1 June 2011) --- Space shuttle Endeavour lands on Runway 15 on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida for the final time. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-112 (1 June 2011) --- Space shuttle Endeavour touches down on Runway 15 on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida for the final time marking the 24th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-111 (1 June 2011) --- Space shuttle Endeavour approaches Runway 15 on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida for the final time marking the 24th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-108 (1 June 2011) --- The crew of STS-134 pose for a photo on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida following the successful landing of space shuttle Endeavour. From left, are European Space Agency astronaut Roberto Vittori, mission specialist; NASA astronauts Greg H. Johnson, pilot; Mark Kelly, commander; Michael Fincke, Greg Chamitoff and Andrew Feustel, all mission specialists. The crew returned to Earth at 2:35 a.m. (EDT) June 1, 2011 on Runway 15, completing a 16-day, 6.5-million mile journey to the International Space Station. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the space station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-083 (1 June 2011) --- Space shuttle Endeavour approaches Runway 15 on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida for the final time. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-071 (1 June 2011) --- Space shuttle Endeavour's drag chute is reflected on the vehicle's tail end as it rolls to a stop on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida for the final time. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-088 (1 June 2011) --- Space shuttle Endeavour rolls to a stop on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida for the final time. Heat from the shuttle's auxiliary power units, which provide hydraulic control, can be seen at the back of Endeavour, near the vertical tail. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-072 (1 June 2011) --- Xenon lights illuminate space shuttle Endeavour's unfurled drag chute as the vehicle rolls to a stop on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida for the final time. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-069 (1 June 2011) --- Xenon lights illuminate space shuttle Endeavour's unfurled drag chute as the vehicle rolls to a stop on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida for the final time. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-073 (1 June 2011) --- Xenon lights illuminate space shuttle Endeavour's unfurled drag chute as the vehicle rolls to a stop on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida for the final time. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-082 (1 June 2011) --- Xenon lights illuminate space shuttle Endeavour's unfurled drag chute as the vehicle rolls to a stop on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida for the final time. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-074 (1 June 2011) --- Space shuttle Endeavour rolls to a stop on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida for the final time. Heat from the shuttle's auxiliary power units, which provide hydraulic control, can be seen at the back of Endeavour, near the vertical tail. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-086 (1 June 2011) --- Space shuttle Endeavour rolls to a stop on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida for the final time. Heat from the shuttle's auxiliary power units, which provide hydraulic control, can be seen at the back of Endeavour, near the vertical tail. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-070 (1 June 2011) --- Xenon lights illuminate space shuttle Endeavour's unfurled drag chute as the vehicle rolls to a stop on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida for the final time. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-066 (1 June 2011) --- Space shuttle Endeavour approaches Runway 15 on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida for the final time. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-085 (1 June 2011) --- Space shuttle Endeavour rolls to a stop on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida for the final time. Heat from the shuttle's auxiliary power units, which provide hydraulic control, can be seen at the back of Endeavour, near the vertical tail. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-084 (1 June 2011) --- Space shuttle Endeavour approaches Runway 15 on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida for the final time. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-076 (1 June 2011) --- Heat from space shuttle Endeavour's auxiliary power units, which provide hydraulic control, can be seen at the back of the shuttle, near the vertical tail. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida, marking the 24th night landing of the Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-075 (1 June 2011) --- Heat from space shuttle Endeavour's auxiliary power units, which provide hydraulic control, can be seen at the back of the shuttle, near the vertical tail. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida, marking the 24th night landing of the Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

STS134-S-081 (1 June 2011) --- Heat from space shuttle Endeavour's auxiliary power units, which provide hydraulic control, can be seen at the back of the shuttle, near the vertical tail. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida, marking the 24th night landing of the Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. (EDT) on June 1, 2011, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. Onboard are NASA astronauts Mark Kelly, STS-134 commander; Greg H. Johnson, pilot; Michael Fincke, Andrew Feustel, Greg Chamitoff and European Space Agency astronaut Roberto Vittori, all mission specialists. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA

CAPE CANAVERAL, Fla. - In Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida, deservicing of space shuttle Endeavour following its STS-130 mission is under way. Endeavour's touchdown at Kennedy's Shuttle Landing Facility following the STS-130 mission to the International Space Station was at 10:20 p.m. EST Feb. 21. Processing now will begin for Endeavour's next flight, STS-134. The six-member STS-134 crew will deliver Express Logistics Carrier 3 and the Alpha Magnetic Spectrometer to the International Space Station, as well as a variety of spare parts including two S-band communications antennas, a high-pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. STS-134 will be the 35th shuttle mission to the station and the 133rd flight in the shuttle program. Launch is targeted for July 29. For information on the STS-134 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts134_index.html. Photo credit: NASA_Kim Shiflett

CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, space shuttle Endeavour arrives outside Orbiter Processing Facility-2. Endeavour's touchdown at Kennedy's Shuttle Landing Facility following the STS-130 mission to the International Space Station was at 10:20 p.m. EST Feb. 21. Processing now will begin for Endeavour's next flight, STS-134. The six-member STS-134 crew will deliver Express Logistics Carrier 3 and the Alpha Magnetic Spectrometer to the International Space Station, as well as a variety of spare parts including two S-band communications antennas, a high-pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. STS-134 will be the 35th shuttle mission to the station and the 133rd flight in the shuttle program. Launch is targeted for July 29. For information on the STS-134 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts134_index.html. Photo credit: NASA_Kim Shiflett

CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, space shuttle Endeavour is towed into Orbiter Processing Facility-2. Endeavour's touchdown at Kennedy's Shuttle Landing Facility following the STS-130 mission to the International Space Station was at 10:20 p.m. EST Feb. 21. Processing now will begin for Endeavour's next flight, STS-134. The six-member STS-134 crew will deliver Express Logistics Carrier 3 and the Alpha Magnetic Spectrometer to the International Space Station, as well as a variety of spare parts including two S-band communications antennas, a high-pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. STS-134 will be the 35th shuttle mission to the station and the 133rd flight in the shuttle program. Launch is targeted for July 29. For information on the STS-134 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts134_index.html. Photo credit: NASA_Kim Shiflett

CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, work platforms are moved into position around space shuttle Endeavour in Orbiter Processing Facility-2. Endeavour's touchdown at Kennedy's Shuttle Landing Facility following the STS-130 mission to the International Space Station was at 10:20 p.m. EST Feb. 21. Processing now will begin for Endeavour's next flight, STS-134. The six-member STS-134 crew will deliver Express Logistics Carrier 3 and the Alpha Magnetic Spectrometer to the International Space Station, as well as a variety of spare parts including two S-band communications antennas, a high-pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. STS-134 will be the 35th shuttle mission to the station and the 133rd flight in the shuttle program. Launch is targeted for July 29. For information on the STS-134 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts134_index.html. Photo credit: NASA_Kim Shiflett

CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, space shuttle Endeavour is towed through the door of Orbiter Processing Facility-2. Endeavour's touchdown at Kennedy's Shuttle Landing Facility following the STS-130 mission to the International Space Station was at 10:20 p.m. EST Feb. 21. Processing now will begin for Endeavour's next flight, STS-134. The six-member STS-134 crew will deliver Express Logistics Carrier 3 and the Alpha Magnetic Spectrometer to the International Space Station, as well as a variety of spare parts including two S-band communications antennas, a high-pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. STS-134 will be the 35th shuttle mission to the station and the 133rd flight in the shuttle program. Launch is targeted for July 29. For information on the STS-134 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts134_index.html. Photo credit: NASA_Kim Shiflett

CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, space shuttle Endeavour arrives in Orbiter Processing Facility-2. Endeavour's touchdown at Kennedy's Shuttle Landing Facility following the STS-130 mission to the International Space Station was at 10:20 p.m. EST Feb. 21. Processing now will begin for Endeavour's next flight, STS-134. The six-member STS-134 crew will deliver Express Logistics Carrier 3 and the Alpha Magnetic Spectrometer to the International Space Station, as well as a variety of spare parts including two S-band communications antennas, a high-pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. STS-134 will be the 35th shuttle mission to the station and the 133rd flight in the shuttle program. Launch is targeted for July 29. For information on the STS-134 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts134_index.html. Photo credit: NASA_Kim Shiflett

CAPE CANAVERAL, Fla. - In Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida, space shuttle Endeavour is ready for preparations to begin for its next mission. Endeavour's touchdown at Kennedy's Shuttle Landing Facility following the STS-130 mission to the International Space Station was at 10:20 p.m. EST Feb. 21. Processing now will begin for Endeavour's next flight, STS-134. The six-member STS-134 crew will deliver Express Logistics Carrier 3 and the Alpha Magnetic Spectrometer to the International Space Station, as well as a variety of spare parts including two S-band communications antennas, a high-pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. STS-134 will be the 35th shuttle mission to the station and the 133rd flight in the shuttle program. Launch is targeted for July 29. For information on the STS-134 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts134_index.html. Photo credit: NASA_Kim Shiflett

CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, workers monitor the placement of space shuttle Endeavour in Orbiter Processing Facility-2. Endeavour's touchdown at Kennedy's Shuttle Landing Facility following the STS-130 mission to the International Space Station was at 10:20 p.m. EST Feb. 21. Processing now will begin for Endeavour's next flight, STS-134. The six-member STS-134 crew will deliver Express Logistics Carrier 3 and the Alpha Magnetic Spectrometer to the International Space Station, as well as a variety of spare parts including two S-band communications antennas, a high-pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. STS-134 will be the 35th shuttle mission to the station and the 133rd flight in the shuttle program. Launch is targeted for July 29. For information on the STS-134 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts134_index.html. Photo credit: NASA_Kim Shiflett

CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, space shuttle Endeavour is towed toward the door of Orbiter Processing Facility-2. Endeavour's touchdown at Kennedy's Shuttle Landing Facility following the STS-130 mission to the International Space Station was at 10:20 p.m. EST Feb. 21. Processing now will begin for Endeavour's next flight, STS-134. The six-member STS-134 crew will deliver Express Logistics Carrier 3 and the Alpha Magnetic Spectrometer to the International Space Station, as well as a variety of spare parts including two S-band communications antennas, a high-pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. STS-134 will be the 35th shuttle mission to the station and the 133rd flight in the shuttle program. Launch is targeted for July 29. For information on the STS-134 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts134_index.html. Photo credit: NASA_Kim Shiflett

CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, U.S. Air Force C-5 aircraft lands at the Shuttle Landing Facility, delivering the ExPRESS Logistics Carrier 3, or ELC-3. ELC-3 and the Alpha Magnetic Spectrometer are the primary payloads for space shuttle Endeavour's STS-134 mission to the International Space Station. The STS-134 crew will also deliver spare parts including two S-band communications antennas, a high pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. Endeavour's launch is targeted for July 29, 2010. For information on the STS-134 mission objectives and crew, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- The crew members of space shuttle Endeavour's STS-134 mission undergo brief medical checks in the Crew Transport Vehicle before talking to media gathered on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown on the Shuttle Landing Facility's Runway 15 was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Mission Specialists Mike Fincke, left, chats with STS-134 Assistant Launch Director Pete Nickolenko following the successful return of space shuttle Endeavour to NASA's Kennedy Space Center in Florida. Endeavour's final return from space completed the 16-day, 6.5-million-mile STS-134 mission. Main gear touchdown on the Shuttle Landing Facility's Runway 15 was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Mission Specialist Greg Chamitoff greets Dana Hutcherson, space shuttle Endeavour's NASA flow manager, after arriving on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida aboard a T-38 jet. While at Kennedy, Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Pilot Greg H. Johnson stands in front of a T-38 jet on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Mission Specialist Michael Fincke listens to Commander Mark Kelly address the media on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- Shuttle Launch Director Mike Leinbach, right, is on hand to greet STS-134 Pilot Greg H. Johnson who arrived on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida aboard a T-38 jet. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Pilot Greg H. Johnson listens to Commander Mark Kelly address the media on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - At the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida, the ExPRESS Logistics Carrier 3, or ELC-3, is removed from the cargo compartment of a U.S. Air Force C-5 aircraft. ELC-3 and the Alpha Magnetic Spectrometer are the primary payloads for space shuttle Endeavour's STS-134 mission to the International Space Station. The STS-134 crew will also deliver spare parts including two S-band communications antennas, a high pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. Endeavour's launch is targeted for July 29, 2010. For information on the STS-134 mission objectives and crew, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Commander Mark Kelly, left, and Mission Specialist Michael Fincke arrive on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida aboard a T-38 jet. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Mission Specialist Michael Fincke prepares to depart the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida aboard a T-38 jet. While at Kennedy, space shuttle Endeavour's crew participated in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training. Fincke will return to NASA's Johnson Space Center in Houston to resume training for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 29 at 3:47 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- Shuttle Launch Director Mike Leinbach, right, is on hand to greet STS-134 Mission Specialist Andrew Feustel who arrived on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida aboard a T-38 jet. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- Media snap photos and record the arrival of space shuttle Endeavour's STS-134 crew members on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. While at Kennedy, Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Commander Mark Kelly stands in front of a T-38 jet on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Pilot Greg H. Johnson, left, and Mission Specialist Roberto Vittori, with the European Space Agency, arrive on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida aboard a T-38 jet. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - At the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida, the ExPRESS Logistics Carrier 3, or ELC-3, is secured on the bed of the truck which will transport it to the Space Station Processing Facility. At left is the U.S. Air Force C-5 aircraft on which it arrived. ELC-3 and the Alpha Magnetic Spectrometer are the primary payloads for space shuttle Endeavour's STS-134 mission to the International Space Station. The STS-134 crew will also deliver spare parts including two S-band communications antennas, a high pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. Endeavour's launch is targeted for July 29, 2010. For information on the STS-134 mission objectives and crew, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Mission Specialist Greg Chamitoff arrives on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida aboard a T-38 jet. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - At the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida, preparations are under way to offload the ExPRESS Logistics Carrier 3, or ELC-3, from a U.S. Air Force C-5 aircraft. ELC-3 and the Alpha Magnetic Spectrometer are the primary payloads for space shuttle Endeavour's STS-134 mission to the International Space Station. The STS-134 crew will also deliver spare parts including two S-band communications antennas, a high pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. Endeavour's launch is targeted for July 29, 2010. For information on the STS-134 mission objectives and crew, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- Shuttle Launch Director Mike Leinbach greets STS-134 Mission Specialist Michael Fincke, who arrived on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida aboard a T-38 jet. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- Shuttle Launch Director Mike Leinbach, right, greets STS-134 Commander Mark Kelly, who arrived on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida aboard a T-38 jet. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Mission Specialist Roberto Vittori, with the European Space Agency, listens to Commander Mark Kelly address the media on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Commander Mark Kelly prepares to depart the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida aboard a T-38 jet. While at Kennedy, space shuttle Endeavour's crew participated in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training. Kelly will return to NASA's Johnson Space Center in Houston to resume training for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 29 at 3:47 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Mission Specialist Greg Chamitoff listens to Commander Mark Kelly address the media on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Commander Mark Kelly addresses the media on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - At the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida, the ExPRESS Logistics Carrier 3, or ELC-3, is offloaded from a U.S. Air Force C-5 aircraft. ELC-3 and the Alpha Magnetic Spectrometer are the primary payloads for space shuttle Endeavour's STS-134 mission to the International Space Station. The STS-134 crew will also deliver spare parts including two S-band communications antennas, a high pressure gas tank, additional spare parts for Dextre and micrometeoroid debris shields. Endeavour's launch is targeted for July 29, 2010. For information on the STS-134 mission objectives and crew, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Pilot Greg H. Johnson prepares to depart the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida aboard a T-38 jet. While at Kennedy, space shuttle Endeavour's crew participated in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training. Johnson will return to NASA's Johnson Space Center in Houston to resume training for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 29 at 3:47 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Commander Mark Kelly arrives on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida aboard a T-38 jet. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- STS-134 Mission Specialist Andrew Feustel listens to Commander Mark Kelly address the media on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. While at Kennedy, space shuttle Endeavour's crew will participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training in preparation for the upcoming STS-134 mission. Endeavour and its six STS-134 crew members will deliver the Express Logistics Carrier-3, Alpha Magnetic Spectrometer-2 (AMS), a high-pressure gas tank, additional spare parts for the Dextre robotic helper and micrometeoroid debris shields to the International Space Station. This will be the final spaceflight for Endeavour. Launch is targeted for April 19 at 7:48 p.m. EDT. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 25th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Sandra Joseph and Kevin O'Connell

CAPE CANAVERAL, Fla. -- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 25th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Tom Farrar and Tony Gray

CAPE CANAVERAL, Fla. -- Streams of smoke trail from the main landing gear tires as space shuttle Endeavour touches down on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida for the final time marking the 25th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Sandra Joseph and Kevin O'Connell

CAPE CANAVERAL, Fla. -- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 25th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Kevin O'Connell

CAPE CANAVERAL, Fla. -- Heat from space shuttle Endeavour's auxiliary power units (APUs), which provide hydraulic control, can be seen at the back of the shuttle, near the vertical tail. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida, marking the 25th night landing of the Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Tom Farrar

CAPE CANAVERAL, Fla. -- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 25th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Tom Farrar and Tony Gray

CAPE CANAVERAL, Fla. -- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 25th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Sandra Joseph and Kevin O'Connell

CAPE CANAVERAL, Fla. -- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 25th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Tom Farrar and Tony Gray

CAPE CANAVERAL, Fla. -- Heat from space shuttle Endeavour's auxiliary power units (APUs), which provide hydraulic control, can be seen at the back of the shuttle, near the vertical tail. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida, marking the 25th night landing of the Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Kenny Allen

CAPE CANAVERAL, Fla. -- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 25th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/George Roberto

CAPE CANAVERAL, Fla. -- Xenon lights help lead space shuttle Endeavour home to NASA's Kennedy Space Center in Florida. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15, marking the 25th night landing of NASA's Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/George Roberto

CAPE CANAVERAL, Fla. -- Heat from space shuttle Endeavour's auxiliary power units (APUs), which provide hydraulic control, can be seen at the back of the shuttle, near the vertical tail. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida, marking the 25th night landing of the Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori. STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Kenny Allen