U.S. space exploration history on U.S. stamps also the only space station NASA launched alone. The 100-ton space station was in Earth's orbit from 1973 to 1979 and it was visited by crews three times in 1973 and 1974. Circling 50 degrees north and south of the equator at an altitude of , Skylab had an orbital period of 93 minutes. There were a plethora of UV astronomy experiments done during the Skylab lifetime, as well as detailed X-ray studies of the Sun. The station was active until July 11, 1979, when it fell out of orbit. The 10-cent Skylab commemorative stamp first day of release took
Chinese large modular space station Chinese large modular space station The Chinese large modular space station is a planned space station to be placed in Low Earth orbit. The planned Chinese Space Station will be roughly one-fifth the mass of the International Space Station and about the size of the decommissioned Russian Mir space station. The Chinese station is expected to have a mass between 80 to 100 metric tons. Operations will be controlled from the Beijing Aerospace Command and Control Center in China. The planned launch date of the core module, the "Tianhe-1" (“Harmony of the Heavens”), is 2020. In 2017, the Chinese launched