Skylab was [[NASA]]'s first orbital laboratory that was operated in 1973 and 1974. <ref>In 1973, the United States launched its first orbital laboratory, Skylab, which was occupied three times for periods of 1 to 3 months. [http://history.nasa.gov/NP-119/ch1.htm NP-119 Science in Orbit], NASA </ref>
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'''Skylab''' was [[NASA]]'s first orbital laboratory. It was operated in 1973 and 1974. <ref>In 1973, the United States launched its first orbital laboratory, Skylab, which was occupied three times for periods of 1 to 3 months. [http://history.nasa.gov/NP-119/ch1.htm NP-119 Science in Orbit], NASA </ref>