Skylab 4 (also SL-4 and SLM-3) was the third Skylab mission and placed the third and final crew aboard the first American space station.
The mission started November 16, 1973 with the launch of three astronauts on a Saturn IB rocket from the Kennedy Space Center, Florida and lasted 84 days, one hour and 16 minutes. A total of 6,051 astronaut-utilization hours were tallied by Skylab 4 astronauts performing scientific experiments in the areas of medical activities, solar observations, Earth resources, observation of the Comet Kohoutek and other experiments.
The manned Skylab missions were officially designated Skylab 2, 3, and 4. Mis-communication about the numbering resulted in the mission emblems reading Skylab I, Skylab II, and Skylab 3 respectively.