The 1959 Selection Process and
the Original Astronauts

The Project Mercury astronauts were chosen after a five-phase, three-month selection process that winnowed 508 Phase 1 candidates (all military test pilots) down to 110 candidates eligible for Phase 2, during which 32 finalists were identified as eligible for further testing. During phases 3 and 4 of the selection process, these 32 men were tested and tested again—first at the Lovelace Clinic in Albuquerque, N.M. (phase 3), and then at the Wright Air Development Center in Dayton, Ohio (phase 4). Of these 32 candidates, 18 numerically ranked men were recommended by the evaluation committee to the STG Selection Board “without medical reservations.”

As the Space Task Group (STG) grew more familiar with its highly motivated candidates, the evaluation committee repeatedly adjusted its early goals and plans. The volunteer rate proved so great at phase 2 (35 men reported to the Pentagon in the first group on Feb. 2, 1959, and 24 of them volunteered) that the committee scrapped its original plans for 12 astronauts.1 “The high rate of interest indicates,” STG member George Low explained, “that few, if any, of the men will drop out during the training process. . . . Consequently, a recommendation has been made to name only six finalists.”2 This recommendation too fell away as evaluation committee members, at phase 5, declared they could not choose only six.

Meeting for the final phase of the historic selection process of 1959, the STG SelectionBoard “found the going so difficult,” according to a NASA history, “that they could notreach the magic number six. So Gilruth decided to recommend seven.”3 The final list ofseven men was reviewed and approved on April 2–3, 1959. Charlie Donlan made thetelephone calls, see the scribbled message handed to Carpenteraboard the USS Hornet on April 3, 1959 at left.

In the Carpenter biography, For Spacious Skies, Kris Stoever reports that the STG Selection Board “chose seven men, but not the top seven. Eschewing to some extent the numerical rankings, they chose the candidates ranked first, second, third, fifth, eighth, tenth,and fifteenth.”4

Navy wags (among them a top Mercury candidate who went on to become the chief of naval operations) suggest that the top seven candidates were, to a man, U.S. marine and navy officers. This would explain, they suggest, both the rather conspicuous balance among the services evident in the final selection of the Mercury astronauts (1 marine, 3 navy, 3 air force) and also in the choices lurching from the top three to the rest of the field (candidates ranked 5, 8, 10, and 15) who had been recommended “without medical reservations.” But surviving members of the evaluation committee, including Dr. Robert B. Voas and Dr. George Ruff, will not confirm this speculation.