Alexei Leonov, a decorated Russian veteran cosmonaut and the first man to have carried out a spacewalk back in 1965, passed away in Moscow at the age of 85.

Leonov has died in Moscow this Friday, according to Russia’s Cosmonaut Training Center officials. The cosmonaut who made history by exiting his capsule for 12 minutes almost 54 years ago will be laid to rest next Tuesday at a federal military cemetery.

A Siberian native, he was one of the 20 Soviet Air Force pilots carefully selected to become part of the first cosmonaut group in 1960 where he made friends with Yuri Gagarin.

The 1965 mission, dubbed Voskhod 2 (or Dawn 2 in English) came amid the contentious space race between the USSR and the United States. Despite an array of glitches – from Leonov having troubles to re-enter the airlock, to his capsule missing the landing zone – the historic flight was considered a success.

Interestingly, Leonov was initially slated to become the first man to land on the Moon, but the costly project was cancelled when the US Apollo crew touched down on the Earth’s satellite in 1969, leaving the Soviets behind.

Still, he pioneered another space endeavor six years later, commanding the Soviet crew during the 1975 Soyuz-Apollo experimental mission, in which the American module was docked to the Soviet one thus forming a temporary space station.

Prominent public figures in Russia commented on Leonov’s passing later in the day, expressing sadness and sympathy for his family. “This is an immeasurable loss,” said cosmonaut Maxim Suraev, who said he was “a living legend.”

RT’s “Earth 360˚” documentary featured Leonov and NASA astronaut Thomas Stafford, commander of the second manned mission to orbit the moon. In the film, the pair, who made history when they shook hands after the successful Apollo-Soyuz docking in 1975, compare their first-hand spaceflight experiences to RT’s SPACEWALK 360, the first-ever panoramic video filmed in open space.

Also on rt.com 1st ever spacewalk relived by Russian cosmonaut in epic 360 VR (VIDEO)

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