Spacemen of fiction - Jules Verne's travelers to the Moon, or the comic strip heroes Flash Gordon and Buck Rogers - were familiar characters midway through the 20th Century, but nobody could describe accurately a real astronaut. There were none.

Then in 1959 the National Aeronautics and Space Administration asked the United States military services to list their members who met specific qualifications. The search was underway for pilots for the exciting new manned space flight program.

In seeking its first space pilots, NASA emphasized jet aircraft flight experience and engineering training, and it tailored physical stature requirements to the small cabin space available in the Mercury capsule then being designed. Basically, those 1959 requirements were: Less than 40 years of age; less than 5ft. 11 inches tall; excellent physical condition; bachelor's degree or equivalent in engineering; qualified jet pilot; graduate of test pilot school, and at least 1500 hours of flying time.

More than 500 hundred men qualified. Military and medical records were examined; psychological and technical tests were given; personal interviews were conducted by psychological and medical specialists. At the end of the first screening, many candidates were eliminated and others decided they did not want to be considered further.

Even more stringent physical and psychological examinations followed, and in April 1959 NASA announced its selection of seven men as the first American astronauts. They were Navy Lieutenant M. Scott Carpenter; Air Force Captains L. Gordon Cooper, Jr., Virgil I. "Gus" Grissom, and Donald K. "Deke" Slayton; Marine Lieutenant Colonel John H. Glenn, Jr., and Navy Lieutenant Commanders Walter M. Schirra, Jr., and Alan B. Shepard, Jr.

Each flew in Project Mercury except Slayton, who was grounded with a previously undiscovered heart condition. After doctors certified that the condition had cleared up, Slayton realized his ambition to fly in space 16 years after his selection. He was a member of the American crew of the Apollo Soyuz Test Project in July 1975, the world's first international manned space flight.

More Recruiting

Three years after that first selection, NASA issued another call for Gemini and Apollo astronaut trainees. Experience in flying high-performance aircraft still was stressed, as was education. The limit on age was lowered to 35 years, the maximum height raised to 6 feet, and the program was opened to qualified civilians. This second recruitment brought in more than 200 applications. The list was screened to 32, then finally pared to nine in September 1962.

Fourteen more astronaut trainees were chosen from nearly 300 applicants in October 1963. By then, prime emphasis had shifted away from flight experience toward superior academic qualifications. In October 1964 applications were invited on the basis of educational background alone. These were the scientist-astronauts, so called because the 400-plus applicants who met minimum requirements had a doctorate or equivalent experience in natural sciences, medicine, or engineering.

These applications were turned over to the National Academy of Sciences in Washington for evaluation. Sixteen were recommended to NASA, and six were selected in June 1965. Although the call for volunteers did not specify flight experience, two of the applicants were qualified jet pilots and did not need the year of basic flight training given the others.

Another 19 pilot astronauts were brought into the program in April 1966, and 11 scientist-astronauts were added in mid-1967. When the Air Force Manned Orbiting Laboratory program was cancelled in mid 1969, seven astronaut trainees transferred to NASA.