The Microgravity Science Laboratory Spacelab module was carried aloft aboard Columbia. Launch occurred on April 4, 1997 2:20 p.m. The mission was planned 16-day mission was cut to just four due to a fuel cell problem. The crew was led by commander Jim Halsell, pilot Susan Still, mission specialists Janice Voss, Don Thomas and Michael Gernhardt and payload specialists Roger Crouch and Greg Linteris.