This was the twenty-third flight of Columbia. This was a reflight of the STS 83 Microgravity Science Laboratory (MSL) mission. MSL was originally launched on April 4, 1997 and was intended to be in orbit for 15 days, 16 hours. The mission was cut short due to a problem with Fuel Cell #2 and Columbia landed on April 8, 19997 after 3 days 23 hours. MSL featured 19 materials science investigations in 4 major facilities. Landed at Kennedy Space Center, FL. July 17, 1997. Mission Duration: 15 days 16 hours 45 minutes 29 seconds. 

Launch Date: July 1, 1997 at 2:02 PM EST Launch Vehicle: Columbia Crew: Commander: James D. Halsell, Pilot: Susan L. Still, Payload Commander: Janice E. Voss, Mission Specialists: Donald A. Thomas, Michael L. Gernhardt, Payload Specialists: Roger Crouch, Greg Linteris

4" diameter