In the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, the external fuel tank for space shuttle Atlantis' STS-125 mission is lowered into high bay 3. It will be installed on the mobile launcher platform and attached to the solid rocket boosters already there. Atlantis' STS-125 mission is the fifth and final shuttle servicing mission to NASA’s Hubble Space Telescope. Launch is targeted for May 12. Photo credit: NASA/Jack Pfaller