STS-1

STS-1 is also an abbreviation for Synchronous Transport Signal (level)-1 in the SONET hierarchy.The first Space Shuttle mission, STS-1, was launched April 12 1981, and returned April 14. Space Shuttle Columbia orbited the earth 36 times in this 54.5-hour mission. It was the first US manned space flight since the Apollo-Soyuz Test Project in July 15 1975.
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