Project Mercury also excluded civilian NASA X-15 pilot Neil Armstrong, though he had been selected by the US Air Force in 1958 for its Man In Space Soonest program, which was replaced by Mercury. Although Armstrong had been a combat-experienced NAP during the Korean War, he left active duty in 1952. Armstrong became NASA's first civilian astronaut in 1962 when he was selected for NASA's second group, and became the first man on the Moon in 1969. It was further stipulated that candidates should be between 25 and 40 years old, no taller than , and hold a college degree in a
Neil Armstrong before extravehicular activity, but Armstrong requested the EVA be moved to earlier in the evening, Houston time. When he and Aldrin were ready to go outside, "Eagle" was depressurized, the hatch was opened, and Armstrong made his way down the ladder. At the bottom of the ladder Armstrong said, "I'm going to step off the LM now". He turned and set his left boot on the lunar surface at 02:56 UTC July 21, 1969, then spoke the now-famous words, "That's one small step for [a] man, one giant leap for mankind." Armstrong prepared his famous epigram on his own. In