Mercury Seven

The Mercury Seven were the group of seven Mercury astronauts announced by NASA on April 9, 1959. They are also referred to as the Original Seven or Astronaut Group 1. They piloted the manned spaceflights of the Mercury program from May 1961 to May 1963. These seven original American astronauts were Scott Carpenter, Gordon Cooper, John Glenn, Gus Grissom, Wally Schirra, Alan Shepard, and Deke Slayton.

Members of the group flew on all classes of NASA manned orbital spacecraft of the 20th century — Mercury, Gemini, Apollo, and the Space Shuttle. Gus Grissom died in 1967, in the Apollo 1 fire. The others all survived past retirement from service. John Glenn went on to become a U.S. senator, and flew on the Shuttle 36 years later to become the oldest person to fly in space. He was the last living member of the class when he died in 2016.

Although NASA planned an open competition for its first astronauts, President Dwight D. Eisenhower insisted that all candidates be test pilots. Because of the small space inside the Mercury spacecraft, candidates could be no taller than 5 feet 11 inches (180 cm) and weigh no more than 180 pounds (82 kg). Other requirements included an age under 40, a Bachelor's degree or equivalent, 1,500 hours of flying time, and qualification to fly jet aircraft.

After an advertisement among military test pilots drew more than 500 applications, NASA searched military personnel records in January 1959 and identified 110 pilots—five Marines, 47 from the Navy, and 58 from the Air Force—who qualified. Sixty-nine candidates were brought to Washington, DC, in two groups; the candidates' interest was so great, despite the extensive physical and mental exams from January to March, that the agency did not summon the last group. The tests included spending hours on treadmills and tilt tables, submerging their feet in ice water, three doses of castor oil, and five enemas. Six candidates were rejected as too tall for the planned spacecraft. Another 33 failed or dropped out during the first phase of exams. Four more refused to take part in the second round of tests, which eliminated eight more candidates, leaving 18.

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