
CAPE CANAVERAL, Fla. - With a rainbow serving as a backdrop in the sky, space shuttle Atlantis (foreground) sits on Launch Pad A and Endeavour on Launch Pad B at NASA’s Kennedy Space Center in Florida. At the left of each shuttle are the open rotating service structures with the payload changeout rooms revealed. The rotating service structures provide protection for weather and access to the shuttle. For the first time since July 2001, two shuttles are on the launch pads at the same time at the center. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis’ upcoming mission to repair NASA’s Hubble Space Telescope, targeted to launch Oct. 10. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. - With a rainbow serving as a backdrop in the sky, space shuttle Atlantis (foreground) sits on Launch Pad A and Endeavour on Launch Pad B at NASA’s Kennedy Space Center in Florida. At the left of each shuttle are the open rotating service structures with the payload changeout rooms revealed. The rotating service structures provide protection for weather and access to the shuttle. For the first time since July 2001, two shuttles are on the launch pads at the same time at the center. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis’ upcoming mission to repair NASA’s Hubble Space Telescope, targeted to launch Oct. 10. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. - Space shuttle Atlantis (foreground) sits on Launch Pad A and Endeavour on Launch Pad B at NASA’s Kennedy Space Center in Florida. At the left of each shuttle are the open rotating service structures with the payload changeout rooms revealed. The rotating service structures provide protection for weather and access to the shuttle. For the first time since July 2001, two shuttles are on the launch pads at the same time at the center. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis’ upcoming mission to repair NASA’s Hubble Space Telescope, targeted to launch Oct. 10. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. - With a crystal blue Atlantic Ocean in the background, space shuttle Endeavour sits on Launch Pad B at NASA’s Kennedy Space Center in Florida. At left of the shuttle is the open rotating service structure with the payload changeout room revealed. The rotating service structures provide protection for weather and access to the shuttle. For the first time since July 2001, two shuttles are on the launch pads at the same time at the center. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis’ upcoming mission to repair NASA’s Hubble Space Telescope, targeted to launch Oct. 10. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. - Clouds serve as a backdrop to frame space shuttle Atlantis (foreground) on Launch Pad A and Endeavour on Launch Pad B at NASA’s Kennedy Space Center in Florida. At the left of each shuttle are the open rotating service structures with the payload changeout rooms revealed. The rotating service structures provide protection for weather and access to the shuttle. For the first time since July 2001, two shuttles are on the launch pads at the same time at the center. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis’ upcoming mission to repair NASA’s Hubble Space Telescope, targeted to launch Oct. 10. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. - Space shuttle Atlantis (foreground) sits on Launch Pad A and Endeavour on Launch Pad B at NASA’s Kennedy Space Center in Florida. At the left of each shuttle are the open rotating service structures with the payload changeout rooms revealed. The rotating service structures provide protection for weather and access to the shuttle. For the first time since July 2001, two shuttles are on the launch pads at the same time at the center. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis’ upcoming mission to repair NASA’s Hubble Space Telescope, targeted to launch Oct. 10. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. - Space shuttle Atlantis (foreground) sits on Launch Pad A and Endeavour on Launch Pad B at NASA’s Kennedy Space Center in Florida. At the left of each shuttle are the open rotating service structures with the payload changeout rooms revealed. The rotating service structures provide protection for weather and access to the shuttle. For the first time since July 2001, two shuttles are on the launch pads at the same time at the center. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis’ upcoming mission to repair NASA’s Hubble Space Telescope, targeted to launch Oct. 10. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. - Space shuttle Atlantis (foreground) sits on Launch Pad A and Endeavour on Launch Pad B at NASA’s Kennedy Space Center in Florida. At the left of each shuttle are the open rotating service structures with the payload changeout rooms revealed. The rotating service structures provide protection for weather and access to the shuttle. For the first time since July 2001, two shuttles are on the launch pads at the same time at the center. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis’ upcoming mission to repair NASA’s Hubble Space Telescope, targeted to launch Oct. 10. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. - With a rainbow serving as a backdrop in the sky, space shuttle Atlantis (foreground) sits on Launch Pad A and Endeavour on Launch Pad B at NASA’s Kennedy Space Center in Florida. At the left of each shuttle are the open rotating service structures with the payload changeout rooms revealed. The rotating service structures provide protection for weather and access to the shuttle. For the first time since July 2001, two shuttles are on the launch pads at the same time at the center. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis’ upcoming mission to repair NASA’s Hubble Space Telescope, targeted to launch Oct. 10. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. –– Seen on Launch Pads 39A and 39B at NASA's Kennedy Space Center in Florida are shuttles on both pads. At left is space shuttle Atlantis, poised for the STS-125 mission targeted to launch May 12, and at right is space shuttle Endeavour. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch May 12 on the STS-125 mission to upgrade NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. –– Space shuttle Atlantis on Launch Pad 39A is viewed across the lagoon at NASA's Kennedy Space Center in Florida. Atlantis is targeted to launch May 12 on the STS-125 mission to upgrade NASA's Hubble Space Telescope. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch May 12 on the STS-125 mission to upgrade NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. –– Space shuttle Atlantis on Launch Pad 39A is viewed across the lagoon at NASA's Kennedy Space Center in Florida. Atlantis is targeted to launch May 12 on the STS-125 mission to upgrade NASA's Hubble Space Telescope. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch May 12 on the STS-125 mission to upgrade NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. –– Dawn breaks over the Atlantic Ocean behind space shuttle Atlantis on Launch Pad 39A at NASA's Kennedy Space Center in Florida. Atlantis is targeted to launch May 12 on its STS-125 mission. Space shuttle Endeavour sits on Launch Pad 39B, probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– Space shuttle Endeavour (left) and space shuttle Atlantis are seen on Launch Pads 39B and 39A, respectively, at NASA's Kennedy Space Center. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010.Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– Early dawn showcases Launch Pads 39A and 39B at NASA's Kennedy Space Center in Florida with shuttles on both pads. At left is space shuttle Atlantis, poised for the STS-125 mission targeted to launch May 12, and at right is space shuttle Endeavour. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following Atlantis' launch. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Chris Rhodes

CAPE CANAVERAL, Fla. –– Launch Pads 39A and 39B at NASA's Kennedy Space Center in Florida are ablaze with lights before dawn, showing shuttles on both pads. At left is space shuttle Atlantis, poised for the STS-125 mission targeted to launch May 12, and at right is space shuttle Endeavour. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following Atlantis' launch. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Chris Rhodes

CAPE CANAVERAL, Fla. – Space shuttle Endeavour stands tall and proud on Launch Pad 39B at NASA's Kennedy Space Center in Florida. First motion of Endeavour's rollout from the Vehicle Assembly Building was at 11:57 p.m. EDT April 16. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – In the Vehicle Assembly Building's High Bay 1 at NASA's Kennedy Space Center in Florida, space shuttle Endeavour is in place for attachment to the external tank and solid rocket boosters on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B on April 17. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. -- This orbiter tribute of space shuttle Atlantis, or OV-104, hangs in Firing Room 4 of the Launch Control Center at NASA's Kennedy Space Center in Florida. In the lower-left corner, it features Atlantis soaring above Earth and threaded through the design are the mission patches for each of Atlantis’ flights. Atlantis' accomplishments include seven missions to the Russian space station Mir and several assembly, construction and resupply missions to the International Space Station. Atlantis also flew the last Hubble Space Telescope servicing mission on STS-125. In the tribute, the planet Venus represents the Magellan probe being deployed during STS-30, and Jupiter represents the Galileo probe being deployed during STS-34. The inset photos illustrate various aspects of shuttle processing as well as significant achievements, such as the glass cockpit and the first shuttle docking with Mir during STS-71. The inset photo in the upper-left corner shows a rainbow over Atlantis on Launch Pad 39A and shuttle Endeavour on Launch Pad 39B at Kennedy. Endeavour was the assigned vehicle had Atlantis’ STS-125 mission needed rescue, and this was the last time both launch pads were occupied at the same time. The stars in the background represent the many people who have worked with Atlantis and their contributions to the vehicle’s success. Graphic design credit: NASA/Amy Lombardo

CAPE CANAVERAL, Fla. – Dawn's early light reveals space shuttle Endeavour secure on Launch Pad 39B at NASA's Kennedy Space Center in Florida. First motion of the rollout from the Vehicle Assembly Building was at 11:57 p.m. EDT April 16. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. - In high bay 1 of the Vehicle Assembly Building at NASA’s Kennedy Space Center, space shuttle Endeavour is lowered alongside its external fuel tank and solid rocket boosters for mating. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is designated the rescue spacecraft for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope, targeted for October. After Atlantis has safely returned from its flight, Endeavour will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station, targeted for November. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - In high bay 1 of the Vehicle Assembly Building at NASA’s Kennedy Space Center, space shuttle Endeavour is lowered alongside its external fuel tank and solid rocket boosters for mating. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is designated the rescue spacecraft for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope, targeted for October. After Atlantis has safely returned from its flight, Endeavour will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station, targeted for November. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - At NASA’s Kennedy Space Center, space shuttle Endeavour is lowered into high bay 1 of the Vehicle Assembly Building for mating with its external fuel tank and solid rocket boosters, waiting below. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is designated the rescue spacecraft for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope, targeted for October. After Atlantis has safely returned from its flight, Endeavour will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station, targeted for November. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - In high bay 1 of the Vehicle Assembly Building at NASA’s Kennedy Space Center, space shuttle Endeavour is lowered alongside its external fuel tank and solid rocket boosters for mating. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is designated the rescue spacecraft for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope, targeted for October. After Atlantis has safely returned from its flight, Endeavour will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station, targeted for November. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - Space shuttle Endeavour is suspended over the transfer aisle of the Vehicle Assembly Building at NASA’s Kennedy Space Center. The shuttle will be lifted into high bay 1 for mating with its external fuel tank and solid rocket boosters. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is designated the rescue spacecraft for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope, targeted for October. After Atlantis has safely returned from its flight, Endeavour will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station, targeted for November. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - At NASA’s Kennedy Space Center, space shuttle Endeavour is slowly lowered into high bay 1 of the Vehicle Assembly Building for mating with its external fuel tank and solid rocket boosters. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is designated the rescue spacecraft for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope, targeted for October. After Atlantis has safely returned from its flight, Endeavour will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station, targeted for November. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. –– Viewed across the lagoon at NASA's Kennedy Space Center in Florida, space shuttle Endeavour is poised on Launch Pad 39B. Surrounding the pad are the lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch May 12 on the STS-125 mission to upgrade NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. –– Under a dawn sky, space shuttle Endeavour is still bathed in light from the fixed service structure. Endeavour joins Atlantis, which is on Launch Pad 39A at NASA's Kennedy Space Center in Florida. The towers around the launch pad were erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. With the space shuttle fleet set for retirement in 2010, this is expected to be the final time two shuttles will be on launch pads at the same time. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– As dawn begins to brighten the sky over Launch Pad 39B at NASA's Kennedy Space Center in Florida, space shuttle Endeavour is seen bathed in lights from the fixed service structure. Endeavour joins Atlantis, which is on Launch Pad 39A. The towers around the launch pad were erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. With the space shuttle fleet set for retirement in 2010, this is expected to be the final time two shuttles will be on launch pads at the same time. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– As dawn begins to brighten the sky over Launch Pad 39B at NASA's Kennedy Space Center in Florida, space shuttle Endeavour is seen bathed in lights from the fixed service structure. Endeavour joins Atlantis, which is on Launch Pad 39A. With the space shuttle fleet set for retirement in 2010, this is expected to be the final time two shuttles will be on launch pads at the same time. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– Dawn rises over the Atlantic Ocean behind space shuttle Endeavour on Launch Pad 39B at NASA's Kennedy Space Center in Florida. Surrounding the pad are the lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Endeavour has joined space shuttle Atlantis, which is on pad 39A. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– Space shuttle Atlantis atop the mobile launcher platform sits on Launch Pad 39A at NASA's Kennedy Space Center in Florida. At left is the Vehicle Assembly Building. Atlantis has been joined by space shuttle Endeavour on Launch Pad 39B. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– Space shuttle Atlantis atop the mobile launcher platform straddles the flame trench on Launch Pad 39A at NASA's Kennedy Space Center in Florida. Behind it is the Atlantic Ocean. Atlantis has been joined by space shuttle Endeavour on Launch Pad 39B. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. – The doors of the Vehicle Assembly Building at NASA's Kennedy Space Center open to reveal space shuttle Atlantis' external fuel tank-solid rocket booster stack in high bay 1. The stack on the mobile launcher platform will be moved to high bay 3 to make room for the ET-SRB stack for space shuttle Endeavour. Atlantis is targeted for launch on the STS-125 mission on May 12 to service NASA's Hubble Space Telescope. Endeavour will fly on the STS-127 mission to the International Space Station and bring the final segments for Japan's Kibo laboratory. Photo credit: NASA/Tim Jacobs

CAPE CANAVERAL, Fla. – Space shuttle Atlantis' external fuel tank-solid rocket booster stack, atop a mobile launcher platform, rolls through the doors of the Vehicle Assembly Building at NASA's Kennedy Space Center into high bay 3. The ET/SRB stack was moved from high bay 1 to make room for the ET-SRB stack for space shuttle Endeavour. Atlantis is targeted for launch on the STS-125 mission on May 12 to service NASA's Hubble Space Telescope. Endeavour will fly on the STS-127 mission to the International Space Station and bring the final segments for Japan's Kibo laboratory. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. – Space shuttle Atlantis' external fuel tank-solid rocket booster stack, atop a mobile launcher platform, rolls away from the Vehicle Assembly Building at NASA's Kennedy Space Center. It is being moved from high bay 1 to high bay 3 to make room for the ET-SRB stack for space shuttle Endeavour. Atlantis is targeted for launch on the STS-125 mission on May 12 to service NASA's Hubble Space Telescope. Endeavour will fly on the STS-127 mission to the International Space Station and bring the final segments for Japan's Kibo laboratory. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. – Space shuttle Atlantis' external fuel tank-solid rocket booster stack, atop a mobile launcher platform, has been rolled out of high bay 1 in the Vehicle Assembly Building at NASA's Kennedy Space Center. It is being moved to high bay 3 to make room for the ET-SRB stack for space shuttle Endeavour. Atlantis is targeted for launch on the STS-125 mission on May 12 to service NASA's Hubble Space Telescope. Endeavour will fly on the STS-127 mission to the International Space Station and bring the final segments for Japan's Kibo laboratory. Photo credit: NASA/Tim Jacobs

CAPE CANAVERAL, Fla. – After moving out of high bay 1 in the Vehicle Assembly Building at NASA's Kennedy Space Center, space shuttle Atlantis' external fuel tank-solid rocket booster stack, atop a mobile launcher platform, rolls into high bay 3. The move makes room in high bay 1 for the ET-SRB stack for space shuttle Endeavour. Atlantis is targeted for launch on the STS-125 mission on May 12 to service NASA's Hubble Space Telescope. Endeavour will fly on the STS-127 mission to the International Space Station and bring the final segments for Japan's Kibo laboratory. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. – Space shuttle Atlantis' external fuel tank-solid rocket booster stack, atop a mobile launcher platform, presents an unusual sight – without the shuttle – as it is transferred from high bay 1 to high bay 3 in the Vehicle Assembly Building at NASA's Kennedy Space Center. It is being moved to high bay 3 to make room for the ET-SRB stack for space shuttle Endeavour. Atlantis is targeted for launch on the STS-125 mission on May 12 to service NASA's Hubble Space Telescope. Endeavour will fly on the STS-127 mission to the International Space Station and bring the final segments for Japan's Kibo laboratory. Photo credit: NASA/Tim Jacobs

CAPE CANAVERAL, Fla. – After moving out of high bay 1 in the Vehicle Assembly Building at NASA's Kennedy Space Center, space shuttle Atlantis' external fuel tank-solid rocket booster stack, atop a mobile launcher platform, rolls toward high bay 3. The move makes room in high bay 1 for the ET-SRB stack for space shuttle Endeavour. Atlantis is targeted for launch on the STS-125 mission on May 12 to service NASA's Hubble Space Telescope. Endeavour will fly on the STS-127 mission to the International Space Station and bring the final segments for Japan's Kibo laboratory. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. – The doors of the Vehicle Assembly Building at NASA's Kennedy Space Center open to reveal space shuttle Atlantis' external fuel tank-solid rocket booster stack in high bay 1. The stack on the mobile launcher platform will be moved to high bay 3 to make room for the ET-SRB stack for space shuttle Endeavour. Atlantis is targeted for launch on the STS-125 mission on May 12 to service NASA's Hubble Space Telescope. Endeavour will fly on the STS-127 mission to the International Space Station and bring the final segments for Japan's Kibo laboratory. Photo credit: NASA/Tim Jacobs

CAPE CANAVERAL, Fla. – Space shuttle Atlantis' external fuel tank-solid rocket booster stack, atop a mobile launcher platform, presents an unusual sight – without the shuttle – as it is transferred from high bay 1 to high bay 3 in the Vehicle Assembly Building at NASA's Kennedy Space Center. It is being moved to high bay 3 to make room for the ET-SRB stack for space shuttle Endeavour. Atlantis is targeted for launch on the STS-125 mission on May 12 to service NASA's Hubble Space Telescope. Endeavour will fly on the STS-127 mission to the International Space Station and bring the final segments for Japan's Kibo laboratory. Photo credit: NASA/Tim Jacobs

CAPE CANAVERAL, Fla. – Space shuttle Endeavour begins its move from Orbiter Processing Facility 2 to the Vehicle Assembly Building at NASA's Kennedy Space Center, Fla. The first motion of the shuttle out of its hangar was at 6:56 a.m. EDT. In the VAB, Endeavour will be lifted into High Bay 1 and mated to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B in about a week. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. – Space shuttle Endeavour arrives at the Vehicle Assembly Building at NASA's Kennedy Space Center, Fla. The first motion of the shuttle out of Orbiter Processing Facility 2 was at 6:56 a.m. EDT. In the VAB, Endeavour will be lifted into High Bay 1 and mated to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B in about a week. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. – In the transfer aisle of the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, cranes raise space shuttle Endeavour to vertical. Endeavour then will be lifted into High Bay 1 and attached to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B on April 17. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – Space shuttle Endeavour is transported from Orbiter Processing Facility 2 to the Vehicle Assembly Building at NASA's Kennedy Space Center, Fla. The first motion of the shuttle out of its hangar was at 6:56 a.m. EDT. In the VAB, Endeavour will be lifted into High Bay 1 and mated to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B in about a week. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. – Space shuttle Endeavour is ready for the rollover from Orbiter Processing Facility 2 to the Vehicle Assembly Building at NASA's Kennedy Space Center, Fla. The first motion of the shuttle out of its hangar was at 6:56 a.m. EDT. In the VAB, Endeavour will be lifted into High Bay 1 and mated to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B in about a week. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. – Workers accompany space shuttle Endeavour as it rolls from Orbiter Processing Facility 2 to the Vehicle Assembly Building at NASA’s Kennedy Space Center, Fla. In the VAB, Endeavour will be lifted into High Bay 1 and mated to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B in about a week. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. – Space shuttle Endeavour is ready for the rollover from Orbiter Processing Facility 2 to the Vehicle Assembly Building at NASA's Kennedy Space Center, Fla. The first motion of the shuttle out of its hangar was at 6:56 a.m. EDT. In the VAB, Endeavour will be lifted into High Bay 1 and mated to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B in about a week. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. – Space shuttle Endeavour rolls into the Vehicle Assembly Building at NASA's Kennedy Space Center, Fla. The first motion of the shuttle out of Orbiter Processing Facility 2 was at 6:56 a.m. EDT. In the VAB, Endeavour will be lifted into High Bay 1 and mated to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B in about a week. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. – In the transfer aisle of the Vehicle Assembly Building at NASA's Kennedy Space Center, Fla., space shuttle Endeavour is in position to be lifted into a high bay. The first motion of the shuttle out of Orbiter Processing Facility 2 was at 6:56 a.m. EDT. In the VAB, Endeavour will be lifted into High Bay 1 and mated to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B in about a week. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. – Space shuttle Endeavour is rolled from Orbiter Processing Facility 2 to the Vehicle Assembly Building at NASA's Kennedy Space Center, Fla. The first motion of the shuttle out of its hangar was at 6:56 a.m. EDT. In the VAB, Endeavour will be lifted into High Bay 1 and mated to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B in about a week. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Jim Grossmann

CAPE CANAVERAL, Fla. –– Sunlight spotlights space shuttle Atlantis (left) and space shuttle Endeavour on Launch Pads 39A and 39B, respectively, at NASA's Kennedy Space Center in Florida. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– Sunlight spotlights space shuttle Atlantis (left) and space shuttle Endeavour on Launch Pads 39A and 39B, respectively, at NASA's Kennedy Space Center in Florida. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– Space shuttle Endeavour (left) and space shuttle Atlantis are seen on Launch Pads 39B and 39A, respectively, at NASA's Kennedy Space Center in Florida. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– Early morning light falls on space shuttle Endeavour on Launch Pad 39B at NASA's Kennedy Space Center in Florida. It joins space shuttle Atlantis on Launch Pad 39A. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– On Launch Pad 39B at NASA's Kennedy Space Center in Florida, space shuttle Endeavour has joined space shuttle Atlantis on Launch Pad 39A. In the background is the Atlantic Ocean. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

Space shuttle Atlantis (left) and space shuttle Endeavour are seen on Launch Pads 39A and 39B, respectively, at NASA's Kennedy Space Center in Florida. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Surrounding pad 39B are the lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Original photo number is KSC-2009-2771.

CAPE CANAVERAL, Fla. –– Space shuttle Atlantis (left) and space shuttle Endeavour are seen on Launch Pads 39A and 39B, respectively, at NASA's Kennedy Space Center in Florida. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Surrounding pad 39B are the lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– Space shuttle Atlantis (left) and space shuttle Endeavour are seen on Launch Pads 39A and 39B, respectively, at NASA's Kennedy Space Center in Florida. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Surrounding pad 39B are the lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– Space shuttle Atlantis atop the mobile launcher platform straddles the flame trench on Launch Pad 39A at NASA's Kennedy Space Center in Florida. It is joined by space shuttle Endeavour on Launch Pad 39B. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– On Launch Pad 39B (left) at NASA's Kennedy Space Center in Florida, space shuttle Endeavour has joined space shuttle Atlantis on Launch Pad 39A. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– Space shuttle Atlantis (left) and space shuttle Endeavour are seen on Launch Pads 39A and 39B, respectively, at NASA's Kennedy Space Center in Florida. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Surrounding the pad are the lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– On Launch Pad 39B at NASA's Kennedy Space Center in Florida, space shuttle Endeavour has joined space shuttle Atlantis on Launch Pad 39A. In the background is the Atlantic Ocean. This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. –– On Launch Pad 39B (left) at NASA's Kennedy Space Center in Florida, space shuttle Endeavour has joined space shuttle Atlantis on Launch Pad 39A (right). This is probably the final time two shuttles will be on launch pads at the same time with the space shuttle fleet set for retirement in 2010. Surrounding pad 39B are the lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. – In the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida space shuttle Endeavour is lifted into the upper levels for transfer to High Bay 1. The shuttle then will be lowered onto the mobile launcher platform and attached to the external fuel tank and solid rocket boosters already installed there. Endeavour is scheduled to roll out to Launch Pad 39B on April 17. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – In the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, space shuttle Endeavour is lowered into High Bay 1 toward the mobile launcher platform for attachment to the external tank and solid rocket boosters already installed on the platform. Endeavour is scheduled to roll out to Launch Pad 39B on April 17. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – In the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, space shuttle Endeavour is lowered into High Bay 1 toward the external tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B on April 17. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – In the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, space shuttle Endeavour is lowered into High Bay 1 toward the mobile launcher platform for attachment to the external tank and solid rocket boosters already installed on the platform. Endeavour is scheduled to roll out to Launch Pad 39B on April 17. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – In the transfer aisle of the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, cranes lift space shuttle Endeavour in order to raise it to vertical. Once vertical, the shuttle will be lifted into High Bay 1, then lowered and attached to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B on April 17. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – Space shuttle Endeavour stands tall and proud on Launch Pad 39B at NASA's Kennedy Space Center in Florida. First motion of Endeavour's rollout from the Vehicle Assembly Building was at 11:57 p.m. EDT April 16. Surrounding the pad (seen left and right) are the new lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – Viewed from below, space shuttle Endeavour is lifted in the upper levels of the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida for transfer to High Bay 1. The shuttle then will be lowered onto the mobile launcher platform and attached to the external fuel tank and solid rocket boosters already installed there. Endeavour is scheduled to roll out to Launch Pad 39B on April 17. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – In the transfer aisle of the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, cranes are fitted onto space shuttle Endeavour to be lifted into High Bay 1. In the high bay, the shuttle will be attached to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B on April 17. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – Space shuttle Endeavour is suspended above the transfer aisle of the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. In this position, it is ready to be lifted into High Bay 1 and attached to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B on April 17. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – The rising sun begins to cast its glow over space shuttle Endeavour on Launch Pad 39B at NASA's Kennedy Space Center in Florida. Behind the shuttle is the new lightning tower erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. First motion of Endeavour's rollout from the Vehicle Assembly Building was at 11:57 p.m. EDT April 16. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – In the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, space shuttle Endeavour is lowered into High Bay 1 toward the external tank and solid rocket boosters already installed on the mobile launcher platform. Endeavour is scheduled to roll out to Launch Pad 39B on April 17. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service the Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch in mid-June. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – Space shuttle Endeavour stands tall and proud on Launch Pad 39B at NASA's Kennedy Space Center in Florida. First motion of Endeavour's rollout from the Vehicle Assembly Building was at 11:57 p.m. EDT April 16. Surrounding the pad (seen left and right) are the new lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. - A rainbow completes this unique panorama of two space shuttles on the launch pads at the same time, the first time since July 2001. At upper right is STS-126 mission’s space shuttle Endeavour, which rolled out Sept. 19. At left is space shuttle Atlantis, preparing for its launch on the STS-125 mission to repair NASA's Hubble Space Telescope, targeted for Oct. 10. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis' upcoming mission. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for the STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo courtesy of NASA.

CAPE CANAVERAL, Fla. –– Sunlight spotlights space shuttle Endeavour poised on Launch Pad 39B at NASA's Kennedy Space Center in Florida. In the foreground is the railway that services Kennedy. Surrounding the pad are the lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch May 12 on the STS-125 mission to upgrade NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – Space shuttle Endeavour, installed on the mobile launcher platform atop the crawler-transporter, moves past the Launch Control Center at NASA's Kennedy Space Center in Florida as it rolls out to Launch Pad 39B. First motion was at 11:57 p.m. EDT April 16. The 4.2-mile journey is expected to take approximately 7 hours. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – Space shuttle Endeavour, installed on the mobile launcher platform atop the crawler-transporter, moves along the crawlerway at NASA's Kennedy Space Center in Florida as it rolls out to Launch Pad 39B. First motion out of the Vehicle Assembly Building was at 11:57 p.m. EDT April 16. The 4.2-mile journey is expected to take approximately 7 hours. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – Space shuttle Endeavour, installed on the mobile launcher platform atop the crawler-transporter, moves out of the Vehicle Assembly Building for rollout to Launch Pad 39B at NASA's Kennedy Space Center in Florida. First motion was at 11:57 p.m. EDT April 16. The 4.2-mile journey is expected to take approximately 7 hours. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – Space shuttle Endeavour, installed on the mobile launcher platform atop the crawler-transporter, arrives on Launch Pad 39B at NASA's Kennedy Space Center in Florida. First motion out of the Vehicle Assembly Building was at 11:57 p.m. EDT April 16. The 4.2-mile journey took approximately 7 hours. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. –– Space shuttle Endeavour is silhouetted against the dawn pink sky on Launch Pad 39B at NASA's Kennedy Space Center in Florida. Surrounding the pad are the lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Dotting the still dark sky at upper right is the moon. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch May 12 on the STS-125 mission to upgrade NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – Just before dawn, space shuttle Endeavour is bathed in xenon lights after being secured on Launch Pad 39B at NASA's Kennedy Space Center in Florida. First motion on rollout from the Vehicle Assembly Building was at 11:57 p.m. EDT April 16. On either side of the pad are two of the new lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. - An aerial view of the Launch Complex at NASA's Kennedy Space Center shows space shuttles on both pads. At top is space shuttle Endeavour, which rolled out Sept. 19, completing the 4.2-mile journey at 6:59 a.m. EDT. In the foreground is space shuttle Atlantis, preparing for its launch on the STS-125 mission to repair NASA's Hubble Space Telescope, targeted for Oct. 10. This is the first time since July 2001 that two shuttles are on the launch pads at the same time at the center. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis' upcoming mission. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for the STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. - An aerial view of the Launch Complex at NASA's Kennedy Space Center shows space shuttles on both pads. At upper right is space shuttle Endeavour, which rolled out Sept. 19, completing the 4.2-mile journey at 6:59 a.m. EDT. In the foreground is space shuttle Atlantis, preparing for its launch on the STS-125 mission to repair NASA's Hubble Space Telescope, targeted for Oct. 10. This is the first time since July 2001 that two shuttles are on the launch pads at the same time at the center. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis' upcoming mission. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for the STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – Space shuttle Endeavour, installed on the mobile launcher platform atop the crawler-transporter, moves out of the Vehicle Assembly Building for rollout to Launch Pad 39B at NASA's Kennedy Space Center in Florida. First motion was at 11:57 p.m. EDT April 16. The 4.2-mile journey is expected to take approximately 7 hours. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. - At NASA’s Kennedy Space Center, space shuttle Endeavour is slowly lifted into the upper levels of the Vehicle Assembly Building for transfer into high bay 1 for mating with its external fuel tank and solid rocket boosters, seen below it. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is designated the rescue spacecraft for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope, targeted for October. After Atlantis has safely returned from its flight, Endeavour will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station, targeted for November. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - Suspended by an overhead crane, space shuttle Endeavour is being raised to a vertical position n the transfer aisle of the Vehicle Assembly Building at NASA’s Kennedy Space Center. The shuttle will be lifted into high bay 1 for mating with its external fuel tank and solid rocket boosters. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is designated the rescue spacecraft for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope, targeted for October. After Atlantis has safely returned from its flight, Endeavour will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station, targeted for November. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - Suspended by an overhead crane, space shuttle Endeavour is being raised to a vertical position in the transfer aisle of the Vehicle Assembly Building at NASA’s Kennedy Space Center. The shuttle will be lifted into high bay 1 for mating with its external fuel tank and solid rocket boosters. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is designated the rescue spacecraft for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope, targeted for October. After Atlantis has safely returned from its flight, Endeavour will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station, targeted for November. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - Suspended over the transfer aisle of the Vehicle Assembly Building at NASA’s Kennedy Space Center, space shuttle Endeavour is slowly lifted into the upper levels for transfer into high bay 1 for mating with its external fuel tank and solid rocket boosters. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is designated the rescue spacecraft for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope, targeted for October. After Atlantis has safely returned from its flight, Endeavour will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station, targeted for November. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Just before dawn, space shuttle Endeavour, installed on the mobile launcher platform atop the crawler-transporter, is secure on Launch Pad 39B at NASA's Kennedy Space Center in Florida. First motion out of the Vehicle Assembly Building was at 11:57 p.m. EDT April 16. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – Just before dawn, space shuttle Endeavour is bathed in xenon lights after being secured on Launch Pad 39B at NASA's Kennedy Space Center in Florida. First motion on rollout from the Vehicle Assembly Building was at 11:57 p.m. EDT April 16. Surrounding the pad are the new lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. - An aerial view south along the seashore shows shuttles on both launch pads. The Atlantic Ocean is a thin line on the horizon. At left is space shuttle Atlantis, preparing for its launch on the STS-125 mission to repair NASA's Hubble Space Telescope, targeted for Oct. 10. At right is space shuttle Endeavour, which rolled out Sept. 19, completing the 4.2-mile journey at 6:59 a.m. EDT. This is the first time since July 2001 that two shuttles are on the launch pads at the same time at the center. Endeavour will stand by at pad B in the unlikely event that a rescue mission is necessary during space shuttle Atlantis' upcoming mission. After Endeavour is cleared from its duty as a rescue spacecraft, it will be moved to Launch Pad 39A for the STS-126 mission to the International Space Station. That flight is targeted for launch Nov. 12. Photo credit: NASA/Troy Cryder

CAPE CANAVERAL, Fla. – Space shuttle Endeavour is raised off the orbiter transporter by an overhead crane in the transfer aisle of the Vehicle Assembly Building at NASA’s Kennedy Space Center. The shuttle will be lifted into high bay 1 for mating with its external fuel tank and solid rocket boosters. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is designated the rescue spacecraft for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope, targeted for October. After Atlantis has safely returned from its flight, Endeavour will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station, targeted for November. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Space shuttle Endeavour, installed on the mobile launcher platform atop the crawler-transporter, moves along the crawlerway at NASA's Kennedy Space Center in Florida as it rolls out to Launch Pad 39B. First motion was at 11:57 p.m. EDT April 16. The 4.2-mile journey is expected to take approximately 7 hours. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. - At NASA’s Kennedy Space Center, a technician (lower left) monitors the progress of space shuttle Endeavour as it is lowered into high bay 1 of the Vehicle Assembly Building for mating with its external fuel tank and solid rocket boosters, waiting below. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is designated the rescue spacecraft for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope, targeted for October. After Atlantis has safely returned from its flight, Endeavour will be moved to Launch Pad 39A for its STS-126 mission to the International Space Station, targeted for November. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. –– Space shuttle Endeavour is silhouetted against the dawn pink sky on Launch Pad 39B at NASA's Kennedy Space Center in Florida. Surrounding the pad are the lightning towers erected for NASA's Constellation Program, which will use the pad for Ares rocket launches. Dotting the dark blue sky at upper right is the moon. Endeavour will be prepared on the pad for liftoff in the unlikely event that a rescue mission is necessary following space shuttle Atlantis' launch May 12 on the STS-125 mission to upgrade NASA's Hubble Space Telescope. After Atlantis is cleared to land, Endeavour will move to Launch Pad 39A for its upcoming STS-127 mission to the International Space Station, targeted to launch June 13. Photo credit: NASA/Jack Pfaller

CAPE CANAVERAL, Fla. – After rolling out of Orbiter Processing Facility 2, space shuttle Endeavour turns toward the Vehicle Assembly Building at NASA's Kennedy Space Center. In the VAB, Endeavour will be attached to its external fuel tank and twin solid rocket boosters. After additional preparations are made, the shuttle will be rolled out to Launch Pad 39B. Endeavour is the backup shuttle, if needed for rescue, for space shuttle Atlantis’ STS-125 mission to NASA’s Hubble Space Telescope targeted for October. Photo credit: NASA/Troy Cryder