cosmonaut

A cosmonaut is a person trained by the Russian space program to command, pilot, or serve as a crew member on human spaceflight missions. The term derives from the Greek kosmos meaning "universe" and nautes meaning "sailor," and it is used primarily in Russia and in space programs influenced by Soviet practice. In English, the term cosmonaut is typically contrasted with astronaut, the term used by the United States and many other nations.

History and notable milestones: The first cosmonaut was Yuri Gagarin, who orbited the Earth aboard Vostok 1 on 12 April 1961. Valentina Tereshkova became the first woman in space in 1963, and Alexei Leonov performed the first spacewalk in 1965. The Intercosmos program, begun in the 1960s, allowed cosmonauts from allied nations to fly aboard Soviet missions.

Training and roles: Cosmonaut candidates undergo extensive, multi-year selection and training to prepare for piloting spacecraft, operating mission hardware, and conducting scientific tasks. Roles include pilot-cosmonaut and research (or engineer) cosmonaut, with training covering spacecraft systems, extravehicular activity, survival, and linguistic skills for international cooperation.

Legacy and current status: Since the dissolution of the Soviet Union, Roscosmos has continued to select and train cosmonauts for missions on Soyuz spacecraft and for expeditions to the International Space Station. While the term cosmonaut remains the standard designation within the Russian space program, the broader international vocabulary often uses astronaut for space travelers.