On April 19, 1971, a Proton rocket lifted off from the Soviet Union's Baikonur Cosmodrome carrying a long silver cylinder no human had ever lived in: Salyut 1, the world's first space station. About the length of a school bus, it had been built to test whether humans could live and work in orbit for weeks at a time. The Soviet Union had quietly leapt ahead of the United States in this new chapter of the Space Race.
Two months later, three cosmonauts - Georgi Dobrovolsky, Vladislav Volkov, and Viktor Patsayev - docked their Soyuz capsule to Salyut 1. They lived aboard for 23 days, running science experiments, exercising on a treadmill, and broadcasting TV greetings to Earth. They were the first humans to live in space outside their own ship. Tragically, on the way home, a valve on their Soyuz failed and depressurised the capsule, and all three died before landing.
Salyut 1 didn't last long in orbit. It re-entered Earth's atmosphere a few months later and burned up over the Pacific. But the basic idea - a permanent home in orbit - changed spaceflight forever. The decades after brought more Salyuts, then Mir, then today's International Space Station, where astronauts have lived continuously since 2000.
