Francis R. Scobee, 46, who flew combat mission in Vietnam, commanded the flight and was making his second space shuttle mission.

Challenger's pilot was Mike Smith, 40, a commander in the U.S. Navy. The Challenger flight was the Vietnam veteran's first space mission.

Ronald E. McNair, 36, an expert on lasers who received a doctorate from MIT, made his first space flight in 1984.

Air Force Lt. Col. Ellison S. Onizuka, 39, a former aerospace engineer and pilot, was a crew member on a secret Department of Defense space shuttle flight last January.

Astronaut Judy Resnik, 36, used the shuttle's robot arm to delicately break away a chunk of ice that built up on the side of the space shuttle Discovery during her first flight in 1984.

Gregory Jarvis, 41, a Hughes Aircraft Co. engineer, was flying on Challenger to conduct tests on the effects of weightlessness on fluid carried in tanks.

Sharon Christa McAuliffe, 37, was selected from 11,146 teachers who applied in NASA's first citizen-in-space competition. In preparation for the flight, she underwent 120 hours of training at the Johnson Space Center.