Fifty-five years ago today, on April 9, 1959, NASA introduced America's first seven astronauts, the Mercury 7, to the public.
The Mercury 7 were military test pilots with college degrees in engineering who were all in excellent physical condition. To be chosen they underwent one of the world's most competitive selection processes, including interviews, written exams, mental evaluations, and stress tests.
Even after selected, they participated in two years of intensive training before risking everything to become the first Americans to rocket into space.
John Glenn is the only living member of the original seven, which included Alan Shepard, Scott Carpenter, Wally Schirra, Gus Grissom, Deke Slayton, and Gordon Cooper.
Selection of the Mercury astronauts began in January 1959. Due to the rigors of space travel, only military test pilots from the U.S. Air Force, Navy, and Marine Corps were considered for America's first manned space program.
110 men from a total of 508 service records screened met the basic requirements.
Candidates had to be younger than 40, no taller than 5' 11", and weigh no more than 180 pounds (due to the small size of the Mercury space capsule). They were also required to hold a bachelor's degree in engineering, have graduated test pilot school, and have 1,500 hours of flying time.
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