File:STS-135 Atlantis is lowered into high bay.jpg

English: In the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, shuttle Atlantis is lowered by an overhead crane into a high bay where it will be attached to its external fuel tank and solid rocket boosters already on the mobile launcher platform. Commander Chris Ferguson, Pilot Doug Hurley and Mission Specialists Sandra Magnus and Rex Walheim are expected to launch in mid-July, taking with them the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts. The STS-135 mission also will fly a system to investigate the potential for robotically refueling existing spacecraft and return a failed ammonia pump module to help NASA better understand the failure mechanism and improve pump designs for future systems. STS-135 will be the 33rd flight of Atlantis, the 37th shuttle mission to the space station, and the 135th and final mission of NASA's Space Shuttle Program.