Salyut 1, the first space station, beat Skylab by two years

Salyut 1, the world’s first space station, was launched by the Soviet Union on 19 April 1971, about two years before America’s Skylab reached orbit in May 1973. It flew on a Proton rocket from Baikonur and was built in a hurry: after Apollo 11, Soviet leaders approved a crash program in February 1970 to fit Soyuz parts to the hull of the secret military Almaz station and launch in under 18 months.

The station was meant to be called Zarya (“dawn”). Ten days before launch, managers renamed it Salyut, because China was developing a spacecraft with the same name and Soviet mission control already used Zarya as its radio call sign. The name was already painted on the module and there was no time to repaint, so it flew labeled Zarya.

In orbit the 66-foot station offered about 3,500 cubic feet of living space, roughly the volume of a large in-ground swimming pool. A cover over its main science instrument failed to jettison, cutting short planned Earth observations.

Getting aboard proved hard. Soyuz 10 reached the station on 24 April but could not make a hard docking and left after 5.5 hours. Engineers redesigned the docking probe, and in June the Soyuz 11 crew of Georgi Dobrovolski, Vladislav Volkov and Viktor Patsayev entered Salyut for a record 24 days; Patsayev turned 38 aboard, the first birthday celebrated in space.

All three died when their capsule depressurized before reentry. Since then cosmonauts have had to wear Sokol pressure suits for launch and landing, a rule still in force. Salyut 1 was steered into the Pacific on 11 October 1971 after 175 days, and its design lives on in the ISS’s Zvezda module.