Story highlights The historic handshake in space in 1975 started collaboration between the U.S. and Russia

New players like China are beginning to explore space

The ISS could act as a buffer zone from international politics, where confrontation gives way to handshakes, writes Monica Grady

Monica Grady is Professor of Planetary and Space Sciences at The Open University. The opinions expressed in this commentary are solely those of the author. CNN is showcasing the work of The Conversation, a collaboration between journalists and academics to provide news analysis and commentary. The content is produced solely by The Conversation.

(CNN) Exactly 40 years ago, a historic handshake took place between Russian cosmonaut Alexey Leonov and U.S. astronaut Tom Stafford during a joint USSR-American docking mission, kicking off a successful collaboration between the two countries in space. That cooperation has lasted, even when relationships on the ground deteriorated. But now that there are more international entrants in the field of space exploration, how firm will the U.S.-Russia bond hold, especially as political tensions rise?

For now, however, U.S. and Russia are still cooperating in space. Some 400km (250 miles) above us, the International Space Station (ISS) is orbiting with three crew members on board -- two Russians and one American. Next week, a rocket launched from the Russian launch facility in Baikonur, Kazakhstan, will carry a Japanese astronaut, plus a third Russian and a second American.

The crew of six will work together until just before Christmas, when they will return to Earth. The ISS is a great example of how international relations should work, and is an active manifestation of the Global Space Exploration Strategy, established in 2007. This is a roadmap for robotic and human exploration of space, endorsed by 14 separate space agencies, including NASA, the European Space Agency and the Russian, Japanese and Chinese counterparts.

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This is a very different picture of space exploration from 50 years ago, when the U.S. and the USSR were firmly gripped in a Cold War and a space race. In 1965, the U.S. was lagging behind the Soviet competition. Still smarting from losing out to Sputnik (the first artificial satellite launched in 1957), Yuri Gagarin (first man in space, 1961) and Valentina Tereshkova (first woman in space, 1963), America focused its efforts on sending a man to the moon.

Part of the drive behind the space race was its mirroring of poor international relations between the U.S. and USSR superpowers. While not actively engaged in direct conflict, the Cold War, the Cuban missile crisis and war in Vietnam all provided opportunities for tension between the two nations. How, then, did we move from international competition to collaboration?

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