The STS-73 Space Shuttle Program Mission Report summarizes the Payload activities as well as the Orbiter, External Tank (ET), Solid Rocket Booster (SRB), Reusable Solid Rocket Motor (RSRM), and the Space Shuttle main engine (SSME) systems performance during the seventy-second flight of the Space Shuttle Program, the forty-seventh flight since the return-to-flight, and the eighteenth flight of the Orbiter Columbia (OV-102). STS-73 was also the first flight of OV-102 following the vehicle's return from the Orbiter Maintenance Down Period (OMDP). In addition to the Orbiter, the flight vehicle consisted of an ET that was designated ET-73; three SSME's that were designated as serial numbers 2037 (Block 1), 2031 (PH-1), and 2038 (Block 1) in positions 1, 2, and 3, respectively; and two SRB's that were designated BI-075. The RSRM's, designated RSRM-50, were installed in each SRB and the individual RSRM's were designated as 36OL050A for the left SRB, and 36OW050B for the right SRB. The primary objective of this flight was to successfully perform the planned operations of the United States Microgravity Laboratory (USML)-2 payload. Fricke, Robert W., Jr. Unspecified Center...