The launch originally set for March 3 was postponed at the T-11 hour mark due to predicted unfavorable weather in the KSC area. The countdown March 4 proceeded smoothly. The only deviation to normal operating procedures was a delay in deploying the solid rocket booster recovery ships because of high seas. Recovery ships left port on launch day, and recovered the boosters and their parachutes on March 6.
Primary payloads were U.S. Microgravity Payload-2 (USMP- 2) and Office of Aeronautics and Space Technology-2 (OAST- 2). USMP-2 included five experiments investigating materials processing and crystal growth in microgravity, while OAST-2 featured six experiments focusing on space technology and spaceflight. Both payloads were located in the payload bay, activated by crew and operated by teams on the ground. USMP-2 experiments received emphasis at beginning of flight; later in mission Columbia’s orbit lowered about 20 nautical miles to facilitate OAST-2 experiments.
Crew worked with experiments located both in middeck and payload bay. These included Dexterous End Effector (DEE), a new magnetic end effector and grapple fixture design being tested for use on remote manipulator system arm; Shuttle Solar Backscatter Ultraviolet/A (SSBUV/A) and Limited Duration Space Environment Candidate Material Exposure (LDCE), all in payload bay. Middeck experiments were Advanced Protein Crystal Growth; Physiological Systems Experiment (PSE); Commercial Protein Crystal Growth (CPCG); Commercial Generic Bioprocessing Apparatus (CGBA); Middeck 0- Gravity Dynamics Experiment (MODE); Bioreactor Demonstration Systems (BDS); Auroral Photography Experiment (APE-B). Air Force Maui Optical Site Calibration Test (AMOS) requires no onboard hardware.
Crew also conducted number of biomedical activities aimed at better understanding and countering effects of prolonged spaceflight.