Space shuttle Discovery is towed from Orbiter Processing Facility-2 to the Vehicle Assembly Building or VAB.

At NASA's Kennedy Space Center in Florida, space shuttle Discovery is towed from Orbiter Processing Facility-2, or OPF-2, to the Vehicle Assembly Building, or VAB. Railings, called strongbacks, are installed along Discovery's payload bay doors to assist with opening and closing of the doors when the shuttle's hydraulic system is not operational and support the doors while they are open.

Discovery will be stored inside the VAB for approximately one month while shuttle Atlantis undergoes processing in OPF-2 following its final mission, STS-135. Discovery flew its 39th and final mission, STS-133, in February and March 2011, and currently is being prepared for public display at the Smithsonian's National Air and Space Museum Steven F. Udvar-Hazy Center in Virginia. For more information about Discovery's Transition and Retirement, visit
www.nasa.gov/mission_pages/shuttle/launch/discovery_rss_collection_archive_1.html. Photo credit: NASA/Frankie Martin