Ralph Morse / Time & Life Pictures / Getty Images a group portrait of the Project Mercury astronauts in their pressure suits on Jan. 1, 1959. Back row from left, Alan B. Shepard Jr., Virgil Ivan Grissom, and Leroy Gordon Cooper Jr.; front row from left, Walter Marty Schirra Jr., Donald Kent Slayton, John Herschel Glenn Jr., and Malcolm Scott Carpenter.

If you were an eager young government employee in the 1950s who wanted to become an astronaut, here’s what you would’ve had to do to qualify.

The U.S. National Archives and Records Administration recently posted the original job description for NASA’s Project Mercury – which in 1961 launched the first American into space – and it’s not for the unfit, Yahoo! News reported.

(MORE: Alan Shepard, 50 Years After Mercury: An Unpredictable NASA Legend)

The 1959 letter written to Lt. Paul B. Bennett Jr. from the technical assistant to the deputy administer, Clotaire Wood, details the various responsibilities required of a Mercury astronaut:

Participates in indoctrination, developmental research and pre-flight training programs under conditions simulating flight profiles of the type expected to be encountered with Project Mercury. Operate and/or observes fixed-base and moving-base simulator tests, serves as subject-under-test, and assists in the analysis of data for the evaluation and development of various boosters and of communication, telemetry, display, vehicle control, environmental-control and other systems involved in launch, atmospheric escape, orbital flight, reentry, landing and recovery. Participates in specialized training exercises such as centrifuge programs to build up tolerances to the motions and forces associated with launch, flight without gravity, and atmospheric reentry, and to develop proficiency and confidence for vehicle operation under such conditions.

The letter was dated June 17, 1959, and according to the U.S. National Archives, NASA announced the selection of its first astronauts — known as the “Mercury Seven” — on April 9, 1959.

On May 5, 1961, Alan Shepard Jr. became the first American in space on the Mercury spacecraft. His suborbital flight, aboard the Freedom 7, lasted 15 min. 28 sec.

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