In 1959, just six months after NASA was established, seven men were selected as the first American astronauts: Alan Shepard, John Glenn, Wally Schirra, Gus Grissom, Deke Slayton, Scott Carpenter and Gordon Cooper.The “Mercury 7” weren’t just average American men. They were all military test pilots, college-educated as engineers and in superb physical condition.
Each man emerged from one of the world’s most competitive selection processes. The five-phase, three-month process included a daunting combination of interviews, written exams, mental evaluations and stress tests.
What followed were two years of intensive training before risking everything to become the first Americans to rocket into space.
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.
30-two men who made it through a tough interview process in Washington, D.C, were sent to Lovelace Clinic in Albuquerque, New Mexico, where psychological and physical tests were conducted.
Test pilots were poked, probed and measured for things like blood volume, water volume and total-body radiation count.
After one week of medical evaluations, the pilots were shipped off to Wright Air Development centre for Phase 4 of the selection program.
Each candidate had to prove his physical endurance through an elaborate series of vibration, heat and pressure tests.
A candidate prepares to be whipped around in a human centrifuge, used to expose astronauts to g-forces they would experience during launch and re-entry.
That month, the Original Seven reported to the Manned Spacecraft centre in Texas (later named the Johnson Space centre), for two years of training.
During the training period, astronauts spent hours in the classroom mastering the details of the Mercury craft and learning more about meteorology and engineering.
Contraptions like the Gimbal Rig simulated an uncontrolled spin in space flight. Nitrogen-gas jets twisted three aluminium cages around at speeds up to 30 revolutions per minute. The pilot was strapped into a plastic seat at the centre of the cage, leaving only his arms free.
To prepare for landing off-course, the astronauts were left in the Nevada desert for four days with a mockup of the Mercury spacecraft, a parachute and a survival scenario. They emerged with clothing made out of the parachute material and beards.
Their training efforts ultimately paid off. On May 5, 1961, Alan Shepard became the first American in space, aboard Freedom 7.
Over the next two years, six of the Original Seven (Slayton was the exception) flew Mercury missions. The five-year-program, which also included five unmanned flights, paved the way for future human space travel.
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