Vostok programme

The Vostok programme (Russian: Восто́к, IPA: [vɐˈstok], Orient or East) was a Soviet human spaceflight project to put the first Soviet citizens into low Earth orbit and return them safely. Competing with the United States Project Mercury, it succeeded in placing the first human, Yuri Gagarin, into space, in a single orbit in Vostok 1 on April 12, 1961. The Vostok capsule was developed from the Zenit spy satellite project and adapted the Vostok launch rocket from the existing R-7 Semyorka intercontinental ballistic missile (ICBM) design. The name "Vostok" was treated as classified information until Gagarin's flight was first publicly disclosed to the world press.

The programme carried out six manned spaceflights between 1961 and 1963. The longest flight lasted nearly five days, and the last four were launched in pairs, one day apart. This exceeded Project Mercury's demonstrated capability of just over 34 hours longest flight, and single missions.

Vostok was succeeded by two Voskhod programme flights in 1964 and 1965, which used three- and two-man modifications of the Vostok capsule and a larger launch rocket.

The world's first artificial satellite, Sputnik 1, had been put into orbit by the Soviets in 1957. The next milestone in the history of space exploration would be to put a human in space, and both the Soviets and the Americans wanted to be the first.

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