The inside of Atlantis' payload bay can be seen from inside the payload changeout room.

The inside of Atlantis' payload bay can be seen from inside 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 orbiter payload bay. At the top of the photo is the orbital docking system. At bottom is the integrated cargo carrier - lite, holding three elements: a nitrogen tank assembly that is part of the external active thermal control system on the International Space Station, the European technology Exposure Facility composed of nine science instruments and an autonomous temperature measurement unit, and the SOLAR payload designed for sun observation. The Columbus Laboratory module will be installed in between. The lab module, built by the European Space Agency, also known as ESA, is approximately 23 feet long and 15 feet wide, allowing it to hold 10 large racks of experiments. Columbus is ESA's largest single contribution to the space station. Columbus will fly to the International Space Station on mission STS-122. The launch is targeted for Dec. 6. Photo credit: NASA/Kim Shiflett