How Space Stations Work

Salyut: the First Space Station

Diagram of the Salyut-4 space station docked to a Soyuz spacecraft
Image courtesy NASA

Russia (then known as the Soviet Union) was the first to place a space station. The Salyut 1 station, which went into orbit in 1971, was actually a combination of the Almaz and Soyuz spacecraft systems. The Almaz system was originally designed for space military purposes, but repurposed for the civilian Salyut space station. The Soyuz spacecraft ferried cosmonauts from Earth to the space station and back.

Salyut 1 was about 45 feet (15 meters) long and held three main compartments that housed dining and recreation areas, food and water storage, a toilet, control stations, exercise equipment and scientific equipment. Initially, the Soyuz 10 crew was supposed to live aboard Salyut 1, but their mission was plagued with docking problems that prevented them from entering the space station. The Soyuz 11 crew was the first crew to successfully live on Salyut 1, which they did for 24 days. However, the crew of Soyuz 11 tragically died upon returning to Earth when the Soyuz 11 capsule depressurized during reentry. Further missions to Salyut 1 were canceled, and the Soyuz spacecraft was redesigned.


After Soyuz 11, the Soviets launched another space station, Salyut 2, but it failed to reach orbit. The Soviets followed with Salyuts 3-5. These flights tested the new Soyuz spacecraft and crews manned these stations for increasingly longer missions. One drawback with these space stations was that they had only one docking port for the Soyuz spacecraft and could not be re-supplied from Earth by other ships.

On Sept. 29, 1977, the Soviets launched Salyut 6. This station had a second docking port where the station could be resupplied by an unmanned docking supply ship called Progress. Salyut 6 operated between 1977 and 1982. In 1982, Salyut 7, the last of the Salyut program was launched. It hosted 11 crews and was inhabited for 800 days. The Salyut program eventually led to the development of Russia's Mir space station, which we will talk about a little later. But first, let's look at America's first space station: Skylab.