Skylab

Forty years ago today, Skylab, America's first space station, was launched.  After a shaky start due to intense vibrations during launch that left Skylab virtually uninhabitable, some brilliant improvisation by NASA and the first crew of astronauts to reach the station saved the project.

Skylab hosted three missions of increasing duration-- 28, 59, and 84 days-- thus proving humans humans could work in space for extended periods.