Project Gemini was NASA‘s second human spaceflight program, conducted between projects Mercury and Apollo. 

The Gemini program defined and tested the skills NASA would need to go to the Moon. Gemini had four main goals: to test an astronaut‘s ability to fly long-duration missions (up to two weeks in space); to understand how spacecraft could rendezvous and dock in orbit around the Earth and the moon; to perfect re-entry and landing methods; and to further understand the effects of longer space flights on astronauts. 

Read more about Project Gemini on NASA.

Left to right: Astronauts John W. Young, Virgil I. Grissom, Walter M. Schirra Jr. and Thomas P. Stafford pose in their spacesuits after being selected for the first Gemini manned mission. Young and Grissom were selected as the prime astronauts and Schirra and Stafford will be the back-up pilots.
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