On 18 March 1965 Russian cosmonaut Alexei Leonov became the first person to perform a spacewalk, when he ventured from his Voskhod spacecraft. The sortie was not without problems: Leonov’s spacesuit expanded in the vacuum of space so much that he was unable to squeeze back into the spacecraft. Taking a hair-raising decision, he opened a valve on the suit to let enough air escape for him to enter the airlock. His spacewalk lasted only 12 minutes but proved that astronauts could work outside a spacecraft.

Less than three months later, American Ed White made the first NASA spacewalk as part of the Gemini 4 mission; it lasted 21 minutes.

The first European to do a spacewalk was the French spationaute Jean-Loup Chrétien, who flew to the Russian Mir space station in 1988. His sortie lasted six hours – a record at the time.

The first spacewalk by an ESA astronaut was made by Thomas Reiter from Mir in 1995 in a Russian Orlan suit. Eleven years later Thomas flew to the International Space Station and performed another spacewalk, this time in NASA’s Extravehicular Mobility Unit, making him one of only two astronauts to use both types.

The most recent spacewalk by an ESA astronaut was Alexander Gerst during his Blue Dot mission in 2014. All ESA astronauts take general spacewalk training to learn how to use the spacesuits and work in weightlessness.

In the 50 years since Leonov’s first spacewalk, more than 200 astronauts from 10 countries have left their spacecraft to work outside.