Soyuz 11 (June 29, 1971). This disaster marks the only time in human history that people died in actual space, and the three cosmonauts who perished also set a then-record for longest time spent in a space station at 22 days. (The Americans broke the cosmonaut’s record in 1973 with Skylab .)

Cold War tensions were beginning to break down, as the two superpowers ushered in a new age of collaboration in space. In the aftermath of the Soyuz 11 disaster, thoughts turned to the investigation and the cause of death. All three crew members had died from suffocation, with the rescue teams having had no chance of saving them.

Soyuz 1 crashed into Earth on April 24, 1967, killing cosmonaut Vladimir Komarov. Komarov was the first fatality in spaceflight and, since his death, has been honored with memorials and monuments near the site of the crash and in Russia for his bravery and skill. Mir-18: Exercise Equipment to the Eye

Soyuz 1 was launched on 23 April 1967 at 00:32 UTC from Baikonur Cosmodrome carrying Komarov, the first Soviet cosmonaut to fly in space twice.

Position                                                        Cosmonaut
Commander                                             Georgy Dobrovolsky
                                                                                               Only spaceflight
Flight Engineer                                         Vladislav Volkov
                                                                                               Second and last spaceflight
Test Engineer                                           Viktor Patsayev
                                                                                               Only spaceflight

Vladimir Mikhaylovich Komarov was a Soviet test pilot, aerospace engineer, and cosmonaut. In October 1964, he commanded Voskhod 1, the first spaceflight to carry more than one crew member. He became the first Soviet cosmonaut to fly in space twice when he was selected as the solo pilot of Soyuz 1, its first crewed test flight. A parachute failure caused his Soyuz capsule to crash into the ground after re-entry on 24 April 1967, making him the first human to die in a space flight.