Georgy Dobrovolsky

Georgiy Timofeyevich Dobrovolsky (Гео́ргий Тимофе́евич Доброво́льский; June 1, 1928 – June 30, 1971) was a Soviet cosmonaut who served on the three-man crew of the Soyuz 11 spacecraft. They became the world's first space station crew aboard Salyut 1, but died in space due to asphyxiation due to an erroneously opened valve. They were the first and, as of 2018, the only humans to have died in space.

Biography
Dobrovolsky, Viktor Patsayev and Vladislav Volkov flew on the Soyuz 11 mission and were the world's second crew to die during a space flight (after Vladimir Komarov in Soyuz 1).

After a normal re-entry, the capsule was opened and the crew was found dead. It was discovered that a valve had opened just prior to leaving orbit that had allowed the capsule's atmosphere to vent away into space, suffocating the crew.

Dobrovolsky's ashes were placed in an urn in the Kremlin Wall Necropolis on Red Square in Moscow. He was posthumously awarded the title of Hero of the Soviet Union, the Order of Lenin and the title of Pilot-Cosmonaut of the USSR.