Space shuttle Discovery rolls on its way from OPF-2 to the Vehicle Assembly Building or VAB.

At NASA's Kennedy Space Center in Florida, space shuttle Discovery -- its nose encased in protective plastic, its cockpit windows covered, and strongbacks attached to its payload bay doors -- rolls past Orbiter Processing Facility-3, or OPF-3, at right, on its way from OPF-2 to the Vehicle Assembly Building, or VAB.

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