The shuttle carrier aircraft or SCA sits on the tarmac at Kennedy Space Center's Shuttle Landing Facility.

The shuttle carrier aircraft, or SCA, sits on the tarmac at Kennedy Space Center's Shuttle Landing Facility after demate from Atlantis. Several service vehicles have arrived to prepare the aircraft for its flight back to Johnson Space Center in Texas. Atlantis arrived at Kennedy Space Center atop the SCA on July 3 after a three-day, cross-country flight due to fuel stops and weather delays. Touchdown was at 8:27 a.m. EDT. Atlantis landed at Edwards Air Force Base in California on June 22 to end mission STS-117. Photo credit: NASA/George Shelton.