One of the world’s most legendary cosmonauts, Alexei Leonov, died today at 85 after a long illness. In 1965, Leonov became the first human being to make a spacewalk and 10 years later commanded the Soviet side of the Apollo-Soyuz Test Project (ASTP), the first U.S.-Soviet space mission. Despite the Cold War, he and his U.S. counterpart, NASA astronaut Tom Stafford, became close friends and remained that way throughout the intervening decades exemplifying how space cooperation can change perspectives and transcend geopolitics.

Coincidentally, Stafford, a retired Air Force Lieutenant General, just spoke at a National Academy of Engineering meeting on Monday where he recalled how his views changed about working with the Soviets and Leonov especially.

“I graduated from the Naval Academy [and] went into the Air Force because the Korean War was going on…. I was a Cold Warrior. I wanted to go to Korea and shoot down MIGs and kill commies. … Then I ended up on Apollo-Soyuz and realized all the Russians weren’t communists. From there Alexei Leonov [became] one of my dearest friends, just like a brother to me.” — Tom Stafford

Leonov entered the record books on March 18, 1965 when he became the first person to make an extravehicular activity (EVA) or spacewalk, exiting from the Voskhod-2 capsule and reentering — with great difficulty – 12 minutes later. As recounted on the National Air and Space Museum’s website, after he was outside the spacecraft, his spacesuit ballooned outward and was too large to fit back in through the hatch. He had to vent some of the air from the suit to get back in.

He recounted the story of those harrowing minutes in an interview with the Fédération Aéronautique Internationale (FAI) on the 50th anniversary of that spacewalk. FAI is the international world air sports federation that confers aeronautical and space records.

Leonov: … After 8 minutes of free floating, I clearly felt the volume of my spacesuit has changed. My fingers [sic] tips no longer felt the glove tips my feet were floating in my boots,… After 2 attempts [to move toward the airlock] I realized, that it wouldn’t work. After calculating the amount of time in light and the oxygen supply left, I decided to drop the pressure inside the spacesuit to 0,27 atm, knowing all the while, that I would reach the threshold of nitrogen boiling in my blood, but I had no choice. … When the pressure dropped, I felt a sense of relief, but during the tasks I changed the method for entering the airlock. I didn’t move with my feet forward as we had practiced, but with my head forward and I managed it. However getting into the airlock was more complicated. I had to turn about to be able to control locking the hatch. Performing these operations I kept constant eye on my camera to ensure it didn’t exit the airlock.

[Interviewer–what is your most vivid memory?]

Leonov: What remain etched in my memory was the extraordinary silence, my heart beating and the difficulty I had breathing.

Russia’s official news agency Tass reported his death today, the same day two NASA astronauts were outside the International Space Station (ISS) doing an EVA, which has become routine since his pioneering mission. During its televised coverage, NASA took a moment to honor his achievements not only in spacewalking, but international cooperation.

Yes, we did take a moment to honor his contributions to space exploration. Here is a link to watch the clip from today’s spacewalk broadcast: https://t.co/c4GCM5vaar — NASA (@NASA) October 11, 2019

Born on May 30, 1934, in Listvyanka, near Lake Baikal in Siberia, Leonov at first planned to become an artist. Instead, however, he joined the military. After qualifying as a parachute instructor in the Soviet Air Force, he was chosen with the first group of cosmonauts in March 1960. Voskhod 2 was his first flight. He hoped to become the first Russian on the Moon, but the Soviet Union cancelled its human lunar landing program after several failures of its N-1 rocket. The Soviets then focused on Earth-orbiting space stations. Leonov was assigned to crews of those early space stations, but was thwarted by a variety of factors. His second and last spaceflight was ASTP.

He retired from the cosmonaut corps in 1991 and became Vice President of Alfa Bank and continued his artistic aspirations. Jonathan McDowell, an astrophysicist at Harvard-SAO and author of Jonathan’s Space Report, was one of the many individuals and organizations paying tribute today via Twitter and included one of Leonov’s most famous paintings — of that groundbreaking 1965 spacewalk.

A Leonov painting of his own spacewalk, from 1990 pic.twitter.com/pCllLOi2JT — Jonathan McDowell (@planet4589) October 11, 2019

Among others tweeting their condolences were Stéphane Israël, the CEO of Arianespace; Ellen Stofan, Director of the National Air and Space Museum; former NASA astronaut Scott Kelly, who holds the record for the longest duration U.S. spaceflight; and Jan Wörner, Director General of the European Space Agency.

#Arianespace is saddened by the loss of a great man of space adventure, @roscosmos cosmonaut Alexei Leonov, the first man to walk in space in 1965. https://t.co/P74D0uVIli — Stéphane Israël (@arianespaceceo) October 11, 2019

So saddened by the loss of #AlexeiLeonov, first spacewalker. He was warm and friendly, and personified why we always need to combine #STEM with the #arts. https://t.co/aa6s0bvyvm — Ellen Stofan (@EllenStofan) October 11, 2019