Challenger was the second shuttle orbiter to fly, after Columbia. Its four-man crew, commanded by Paul Weitz, deployed the TDRS-1 communications satellite, whose upper-stage booster malfunctioned and left it in the wrong orbit; controllers spent months nudging it into place with small thrusters. On April 7, Story Musgrave and Donald Peterson made the first spacewalk of the shuttle program. Challenger flew nine missions before it broke apart 73 seconds after launch in January 1986.
Challenger began life as a structural test article, a vehicle built to be shaken and stressed on the ground, and NASA converted it to fly rather than build a new orbiter from scratch. Its first launch, planned for January 1983, was delayed for months by hydrogen leaks in its main engines. It finally lifted off from Launch Complex 39A at 1:30 p.m. Eastern time on April 4, 1983.
The mission's cargo was TDRS-1, the first of a constellation of satellites meant to relay communications between spacecraft and the ground, replacing a patchwork of ground stations. After release, its Inertial Upper Stage booster tumbled during its second burn and stranded the satellite in a low, elliptical orbit. Engineers spent the next several months using its tiny attitude-control thrusters to raise it to geostationary altitude, an improvised rescue that worked.
On the mission's fourth day, Story Musgrave and Donald Peterson spent about four hours in the payload bay testing the new spacesuits and tools, the first American spacewalk in nine years. Challenger landed at Edwards Air Force Base on April 9.
Key people: Paul J. Weitz, Karol J. Bobko, Story Musgrave, Donald H. Peterson