Voskhod 2 carried Alexei Leonov on the first spacewalk on 18 March 1965.
Leonov left the spacecraft through an inflatable airlock and spent about 12 minutes outside, connected to the capsule by a tether. His spacesuit inflated in the vacuum, making it difficult to re-enter the airlock. He had to reduce the suit’s internal pressure before returning safely.
The mission was commanded by Pavel Belyayev and lasted just over 26 hours. Its main achievement demonstrated that a human could work outside a spacecraft, an ability later needed for lunar exploration, satellite repair, and space-station construction.
Voskhod 2’s return was also difficult. A guidance problem caused the crew to land far from the planned site, and they spent a night in a snowy forest before rescuers arrived. The mission is sometimes confused with Gemini 4, during which Ed White performed the first American spacewalk.