At Launch Pad 39A the payload canister is lifted from its transporter toward the payload changeout room in the rotating service structure.

At Launch Pad 39A at NASA's Kennedy Space Center in Florida, the payload canister, at left, is lifted from its transporter toward the payload changeout room in the rotating service structure. The canister carries a cargo of four carriers holding various equipment for the STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope. Atlantis is seen at right, atop the mobile launcher platform. The two tail service masts flank the engines in front of the wings. At the pad, the cargo will be moved into the Payload Changeout Room. The changeout room is the enclosed, environmentally controlled portion of the rotating service structure that supports cargo delivery to the pad and subsequent vertical installation into the shuttle’s payload bay. Launch of Atlantis is targeted for Oct. 10. Photo credit: NASA/Troy Cryder