The Space Shuttle Columbia stands poised after the Rotating Service Structure of Launch Pad 39A has been moved back.

The Space Shuttle Columbia stands poised in the night for the STS-83 Microgravity Science Laboratory-1 (MSL-1) mission after the Rotating Service Structure of Launch Pad 39A has been moved back prior to the start of fueling operations that take place about 12 hours before liftoff. During the scheduled 16-day STS-83 mission, the MSL-1 will be used to test some of the hardware, facilities and procedures that are planned for use on the International Space Station as well as research in combustion, protein crystal growth and materials processing experiments