Cosmonaut Alexei Leonov, leaving his spacecraft Voskhod 2 for 12 minutes, becomes the first person to walk in space.

An astronaut is a person trained, equipped, and deployed by a human spaceflight program to serve as a commander or crew member of a spacecraft. Although generally reserved for professional space travelers, the term is sometimes applied to anyone who travels into space, including scientists, politicians, journalists, and space tourists.

Alexei Arkhipovich Leonov was a Soviet and Russian cosmonaut and aviator, Air Force major general, writer, and artist. On 18 March 1965, he became the first person to conduct a spacewalk, exiting the capsule during the Voskhod 2 mission for 12 minutes and 9 seconds. He was also selected to be the first Soviet person to land on the Moon although the project was cancelled.

Voskhod 2 was a Soviet crewed space mission in March 1965. The Vostok-based Voskhod 3KD spacecraft with two crew members on board, Pavel Belyayev and Alexei Leonov, was equipped with an inflatable airlock. It established another milestone in space exploration when Alexei Leonov became the first person to leave the spacecraft in a specialised spacesuit to conduct a 12-minute spacewalk.

Extravehicular activity (EVA) is any activity done by an astronaut in outer space outside a spacecraft. In the absence of a breathable Earthlike atmosphere, the astronaut is completely reliant on a space suit for environmental support. EVA includes spacewalks and lunar or planetary surface exploration. In a stand-up EVA (SEVA), an astronaut stands through an open hatch but does not fully leave the spacecraft. EVAs have been conducted by the Soviet Union/Russia, the United States, and China; astronauts from Canada, Japan, Brazil, the United Arab Emirates, and the European Space Agency have also participated in EVAs conducted by those nations.