McDivitt was in the Air Force; selected as a member of the second group of astronauts in 1962, he was command pilot of Gemini 4 (1965). Scott, also Air Force, was selected in the third astronaut group in 1963 and flew alongside Neil Armstrong in Gemini 8, on which the first spacecraft docking was performed. Schweickart, a civilian who had served in the Air Force and Massachusetts Air National Guard, was selected as a Group3 astronaut but was not assigned to a Gemini mission and had no spaceflight experience.