Editing STS-9 (section)

== Mission summary ==
[[File:Sts-9lift.jpg|thumb|upright=1.0|left|STS-9 launches from Kennedy Space Center, on November 28, 1983.]]

STS-9 launched successfully from [[Kennedy Space Center]] at 11:00:00 a.m. EST on November 28, 1983. The shuttle's crew was divided into two teams, each working 12-hour shifts for the duration of the mission. Young, Parker and Merbold formed the Red Team, while Shaw, Garriott and Lichtenberg made up the Blue Team. Usually, Young and Shaw were assigned to the flight deck, while the mission and payload specialists worked inside the Spacelab.

Over the course of the mission, 72 scientific experiments were carried out, spanning the fields of atmospheric and [[plasma physics]], [[astronomy]], [[solar physics]], [[material science]]s, [[technology]], [[astrobiology]] and [[Earth observation]]s. The Spacelab effort went so well that the mission was extended an additional day to 10 days, making it the longest-duration shuttle flight at that time. In addition, Garriott made the first [[ham radio]] transmissions by an [[amateur radio]] operator in space during the flight. This led to many further space flights incorporating amateur radio as an educational and back-up communications tool.

The Spacelab 1 mission was highly successful, proving the feasibility of the concept of carrying out complex experiments in space using non-NASA persons trained as payload specialists in collaboration with a POCC. Moreover, the [[TDRS-1]] satellite, now fully operational, was able to relay significant amounts of data through its ground terminal to the POCC.

During orbiter orientation, four hours before re-entry, one of the [[Fly-by-wire|flight control]] computers crashed when the [[Reaction Control System]] (RCS) thrusters were fired. A few minutes later, a second crashed in a similar fashion, but was successfully rebooted. Young delayed the landing, letting the orbiter drift. He later testified: "Had we then activated the Backup Flight Software, loss of vehicle and crew would have resulted". Post-flight analysis revealed the GPCs ''(General Purpose Computers)''<ref>{{cite web|url=http://www.spaceshuttleguide.com/system/data_processing_system.htm|title=Space Shuttle DATA PROCESSING SYSTEM Manual; Interior of the Flight Deck of the Space Shuttles}}</ref> failed when the RCS thruster motion knocked a piece of [[solder]] loose and shorted out the CPU board. A GPC running BFS may or may not have the same soldering defect as the rest of the GPCs. Switching the vehicle to the BFS from normal flight control can happen relatively instantaneously, and that particular GPC running the BFS could also be affected by the same failure due to the soldering defect. If such a failure occurred, switching the vehicle back to normal flight control software on multiple GPCs from a single GPC running BFS takes a lot longer, in essence leaving the vehicle without any control at all during the change.

''Columbia'' landed on Runway 17 at [[Edwards Air Force Base]] on December 8, 1983, at 03:47:24 p.m. [[Pacific Time Zone|PST]], having completed 167 orbits and travelled {{convert|6.9|e6km|e6mi|order=flip|abbr=off}} over the course of its mission. Right before landing, two of the orbiter's three [[auxiliary power unit]]s (APUs) caught fire due to a [[hydrazine]] leak, but the orbiter nonetheless landed successfully. ''Columbia'' was ferried back to KSC on December 15, 1983. The leak was later discovered after it had burned itself out and caused major damage to the compartment. By this time, ''Discovery'' had been delivered just three weeks before the launch of STS-9. This allowed NASA to take ''Columbia'' out of service for an extensive renovation and upgrade program to bring it up to date with ''Challenger'' as well as ''Discovery'' and later on ''Atlantis'', which would be delivered in 1985. As a result, ''Columbia'' would not fly at all during 1984–1985.