Gemini Project

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Project Gemini was the second American human spaceflight program, following Mercury program. Gemini started in 1961 and ended by 1966. The crew consisted of two astronauts. Generally the main aim of the projects was to develop the space techniques to help to land the astronauts on the Moon.

NASA
While the Apollo program was chartered on May 25, 1961 it became clear that Mercury program should be followed by another program to develop spaceflight capability to support Apollo program. The program was named Gemini, coming from Latin name for twins, which was reflecting that space flight was designed for 2 astronauts onboard.

Among main objectives of the mission belong to show endurance of humans during longer time of the space flight required for the Moon landing between 8 and 14 days, to perform space walks and tasks there, and to demonstrate docking with another vehicle in space.

 Each flight had a primary crew and backup crew. The backup crew came to primary crew three flights later. 16 astronauts flew on 10 Gemini missions.
Astronaut group 1 consisted of 3 Mercury astronauts: Cooper, Grissom, Schirra.
Group 2 consisted of 8 astronauts Armstrong, Borman, Conrad, Lovell, McDivitt, Stafford, White, Young.  The new challenges of rendezvous and lunar landing resulted in selecting new candidates with engineering degrees as well as test pilot experiences.
Group 3 consisted of 5 astronauts where was required test pilot experience Aldrin, Cernan, Collins, Cordon, Scott. 

Most of the astronauts were planned and trained for Apollo program. 

Unmanned missions:
Gemini 1 First test flight 8–12 April 1964
Gemini 2 Suborbital flight to test heat shield 19 January 1965 (duration about 18 min)

 Manned missions:
Gemini 3 crew was Grissom and Young, 23 March 1965 (duration almost 5 hours, 3 orbits)
Gemini 4 crew was McDivitt and White , 3–7 June 1965 (duration almost 4 days, White's "space walk" was a 22-minute)
Gemini 5 crew was Cooper and Conrad, 21–29 August 1965 (duration almost 8 days)
Gemini 6 - Gemini VI mission was scrubbed because the launch of its Agena docking target failed
Gemini 7  crew was Borman and Lowell, 4–18 December 1965 (duration almost 14 days)
Gemini 6-A crew was Schirra and Sttaford, 15–16 December 1965 (duration 1 day, first space rendezvous performed between Gemini 6-A and Gemini 7, station-keeping for over five hours at the distance between from 0.30 to 91 m)
Gemini 8 crew was Armstrong and Scott, 16–17 March 1966 (duration about 10 hours and Accomplished first docking with another space vehicle)
Gemini 9-A crew was Stafford and Cernan, 3–6 June 1966 (duration about 3 days)
Gemini 10 crew was Young and Collins, 18–21 July 1966 (duration almost 3 days, first use of the Agena Target Vehicle's propulsion systems)
Gemini 11 crew was Conrad and Gordon, 12–15 September 1966 (duration almost 3 days)
Gemini 12 crew was Lowell and Aldrin, 11–15 November 1966 (duration almost 4 days, rendezvoused and docked manually with its target Agena)

   

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