Skylab was a space station operated by the United States from 1973 to 1979. The two-story Skylab was much larger than its contemporary Salyut space stations. It was 118 feet (36 meters) long, 21 feet (6.4 meters) in diameter, and weighed eighty tons. It contained a workshop, living quarters for three people, a module with multiple docks, and a solar observatory. At an altitude of 270 miles (440 kilometers), Skylab holds the record for the largest orbital distance from Earth’s surface of any human-occupied space station.