This payload canister is being transported to Launch Pad 39A for a fit check.

This payload canister is being transported to Launch Pad 39A for a "fit check." At a later date, the canister will be used to transport to the pad the S3/S4 solar arrays that are the payload for mission STS-117. The mission will launch on Space Shuttle Atlantis for the 21st flight to the International Space Station, and the crew of six will continue the construction of station with the installation of the arrays. The launch of Atlantis is targeted for March 16. Photo credit: NASA/George Shelton