On this day in space! June 29, 1971: 3 cosmonauts lost in Soyuz 11 tragedy

News
By last updated

On June 29, 1971, a Soviet space mission ended in tragedy when three Russian cosmonauts were found dead inside their spacecraft after returning to Earth.

On June 29, 1971, a Soviet space mission ended in tragedy when three Russian cosmonauts were found dead inside their spacecraft after returning to Earth.

Inside the Soyuz 11 space capsule were cosmonauts Vladislav Nikolayevich, Viktor Ivanovich Patsayev, and Georgi Timofeyevich Dobrovolskiy. They were the only crew to ever board the world's first space station, Salyut 1.

Soviet cosmonauts Georgi Dobrovolski, Vladislav Volkov and Viktor Patsayev of the Soyuz 11 space mission, June 1971. (Image credit: Roscosmos)

They launched on June 6, 1971 and spent 23 days doing science experiments aboard the space station before heading back to Earth. The reentry seemed to be going according to plan until the recovery team opened the capsule.

Investigators believe the crew had become asphyxiated when a ventilation valve rattled open, causing the cabin to depressurize.

On This Day in Space: See our full 365-day video archive!

You must confirm your public display name before commenting

Please logout and then login again, you will then be prompted to enter your display name.

Hanneke Weitering
Hanneke Weitering
Contributing expert

Hanneke Weitering is a multimedia journalist in the Pacific Northwest reporting on the future of aviation at FutureFlight.aero and Aviation International News and was previously the Editor for Spaceflight and Astronomy news here at Space.com. As an editor with over 10 years of experience in science journalism she has previously written for Scholastic Classroom Magazines, MedPage Today and The Joint Institute for Computational Sciences at Oak Ridge National Laboratory. After studying physics at the University of Tennessee in her hometown of Knoxville, she earned her graduate degree in Science, Health and Environmental Reporting (SHERP) from New York University. Hanneke joined the Space.com team in 2016 as a staff writer and producer, covering topics including spaceflight and astronomy. She currently lives in Seattle, home of the Space Needle, with her cat and two snakes. In her spare time, Hanneke enjoys exploring the Rocky Mountains, basking in nature and looking for dark skies to gaze at the cosmos.