Neil Armstrong was an astronaut on Gemini 8.
Gemini 8 . Command pilot Neil Armstrong 's flight marked the second time a U.S. civilian flew into space ( Joseph Albert Walker became the first U.S. civilian on X-15 Flight 90 ) . Neil Alden Armstrong ( August 5 , 1930 -- August 25 , 2012 ) was an American astronaut and the first person to walk on the Moon . He made his first space flight as command pilot of Gemini 8 in March 1966 , becoming NASA 's first civilian astronaut to fly in space .