At NASA's Kennedy Space Center in Florida External Tank-135 is transported to the Vehicle Assembly Building in the background.

At NASA's Kennedy Space Center in Florida, External Tank-135 is transported to the Vehicle Assembly Building in the background. The tank arrived in Florida on Dec. 26 aboard the Pegasus barge, towed by a solid rocket booster retrieval ship from NASA's Michoud Assembly Facility near New Orleans.

ET-135 will be used to launch space shuttle Discovery on the STS-131 mission to the International Space Station. Launch is targeted for March 18. For information on the components of the space shuttle and the STS-131 mission, visit http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts131/index.html. Photo credit: NASA/Jack Pfaller