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
Aurora Space Station Aurora Space Station The Aurora Space Station is a technology concept for a private commercial space station in low Earth orbit that was announced on 5 March 2018 by Orion Span, a startup aerospace company in California, USA. The concept envisions a capacity of six people: two crew and four tourists. No launch contract has been signed for deployment of the modules nor crewed vehicles, and its construction has not started, but its representatives claim it will be launched in 2021. Frank Bunger, the founder and CEO of Orion Span, stated that the Aurora Station would offer to space tourists