Elderly US astronauts reunited with their Soviet-era counterparts in Moscow on Wednesday to mark the 35th anniversary of their epic "handshake in space" in 1975 at the height of the Cold War.
Apollo astronauts Tom Stafford and Vance Brand joked with Soyuz cosmonaut Alexei Leonov over their troubles communicating after the initial exuberant greetings shouted out when the two space crafts docked on July 17, 1975.
The images of the handshake between the three men as the hatches opened were beamed around the world, marking the start of the East-West space cooperation following years of gruelling planning between the Cold War foes.
"We had three official space languages: English, Russian and the language of (the US state of) Oklahoma," Leonov, 76, poked fun at Stafford's southern US accent.
Leonov, a legendary figure in the history of space exploration, was the first man ever to make a space walk in 1965.
Stafford, the 79-year-old veteran Apollo commander, in turn said learning Russian was the most challenging feat of his career.
"The Apollo-Soyuz mission was my fourth mission. I had flown three previously, one stop to the moon and back... so technically Apollo-Soyuz to me was somewhat simple," Stafford told reporters in Moscow.
"But the most difficult thing of all the missions I flew was learning the Russian language.
"I knew that when I opened the hatch and met Alexei I had to speak Russian as well as he spoke English and with my Oklahoma accent that was very difficult," he said.
Brand, 79, said that language slip-ups were fodder for many shared jokes, which helped surmount deeper divide between the long-time rivals.
"We laughed a lot (over our mistakes). But looking at the big picture we were breaking new ground," he said. "Back then everything was much different, our cultures were very different."
"And from a technical stand point our space programmes grew up like two trees with two very different roots."
The space mission showed that a thaw in US-Soviet relations was possible back on Earth, Stafford said, delighting the audience in Moscow by speaking in halting Russian.
"The Soyuz flight was a historic flight. It is a symbol, a very important symbol for the world. In space, we forged very warm relations and we showed it was possible to live in this way back on earth," he said.
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