STS073-108-005 (20 October-5 November 1995) --- Two members of the crew perform an in-flight maintenance on the Drop Physics Module (DPM) in the science module aboard the Earth-orbiting Space Shuttle Columbia. Payload commander Kathryn C. Thornton and payload specialist Albert Sacco Jr. were part of a seven-member crew that spent 16 full days in space in support of the United States Microgravity Laboratory (USML-2) mission.