The first time a human stepped outside of a spacecraft was March 18, 1965, when cosmonaut Alexei Leonov took a leap of faith and science. Russian space agency Roscosmos announced Friday that Leonov has died in Russia at the age of 85.
"One of the first cosmonauts of the world space era, Alexei Leonov was committed to his Motherland and his cause, his name is lettered in gold in the world space exploration history," Roscosmos said. His cause of death hasn't been released, but he had reportedly dealt with a long illness.
Leonov spent 12 minutes tethered to the capsule during the Voskhod 2 mission in 1965. The effort almost ended in disaster when his spacesuit expanded. He had to release pressure from the suit in order to squeeze back into the airlock at the end of the spacewalk.
Leonov stayed in touch with both Roscosmos and NASA space exploration efforts long after his retirement in the early '90s. Earlier this year, International Space Station cosmonauts recorded birthday greetings for Leonov in space.
NASA paid tribute to Leonov on Friday. "His venture into the vacuum of space began the history of extravehicular activity that makes today's Space Station maintenance possible," NASA tweeted.
Spacewalks are now a routine part of space work. Two NASA astronauts are conducting one Friday outside the ISS to install new batteries.
Leonov recounted the beautiful and harrowing experience of his spacewalk mission in the book Two Sides of the Moon, co-written with NASA Apollo astronaut David Scott.
Leonov's post-mission report in 1965 was short: "Provided with a special suit, man can survive and work in open space. Thank you for your attention."