Skylab was the first United States space station, launched by NASA, occupied for about 24 weeks between May 1973 and February 1974. It was operated by three separate three-astronaut crews: Skylab 2, Skylab 3, and Skylab 4. Major operations included an orbital workshop, a solar observatory, Earth observation, and hundreds of experiments. Unable to be re-boosted by the Space Shuttle, which was not ready until 1981, Skylab's orbit eventually decayed, and it disintegrated in the atmosphere on July 11, 1979, scattering debris across the Indian Ocean and Western Australia.
In the 60s "Astronaut happiness wasn’t a factor” says historian David Hitt. On Skylab 4, in 1973, the crew was overworked with packed schedules each day. They told NASA they couldn't keep up. This event is misreported as a "mutiny," but it had big effects. Astronauts now work 9-5, with weekends off.