Rear Admiral Alan Shepard (1923-1998) was an American astronaut, naval aviator and test pilot. In 1961 he became the first American to travel into space and in 1971 he walked on the Moon.
John Glenn (1921-2016) was a United States Marine Corps aviator, engineer and astronaut. He was the first American to orbit the Earth. Following his retirement from NASA, he served as a U.S. Senator for Ohio from 1974 to 1999.
Neil Armstrong (1930-2012) was an American astronaut and aeronautical engineer. He was the first person to walk on the Moon, in July 1969 on the Apollo 11 mission.