Project Gemini (1961–66)

Based on studies to grow the Mercury spacecraft capabilities to long-duration flights, developing space rendezvous techniques, and precision Earth landing, Project Gemini was started as a two-man program in 1962 to overcome the Soviets' lead and to support the Apollo manned lunar landing program, adding extravehicular activity (EVA) and rendezvous and docking to its objectives. The first manned Gemini flight, Gemini 3, was flown by Gus Grissom and John Young on March 23, 1965.^[30] Nine missions followed in 1965 and 1966, demonstrating an endurance mission of nearly fourteen days, rendezvous, docking, and practical EVA, and gathering medical data on the effects of weightlessness on humans.^[31][32]

Under the direction of Soviet Premier Nikita Khrushchev, the USSR competed with Gemini by converting their Vostok spacecraft into a two- or three-man Voskhod. They succeeded in launching two manned flights before Gemini's first flight, achieving a three-cosmonaut flight in 1963 and the first EVA in 1964. After this, the program was canceled, and Gemini caught up while spacecraft designer Sergei Korolevdeveloped the Soyuz spacecraft, their answer to Apollo.

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