It's been four years since NASA put out a recruitment call for more astronauts, but on Wednesday the U.S. space agency said it would be hiring again soon.
A two-month application period opens Dec. 14.
The agency hired just eight astronaut candidates during its last recruitment. Applicants who didn't make the cut were in good company – nearly 6,400 people applied for the job.
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NASA currently has 47 astronauts available for flight assignments – less than one-third the size of the corps in 1999 at the peak of the shuttle program.
Typically, crews of six or seven flew on the space shuttle, with missions slated every two or three months. Now, just two to four NASA astronauts fly each year to staff the International Space Station.
Their numbers will be growing. In 2018, NASA expects to add an additional member to the live-aboard station crew. Agency astronauts also will participate in test flights of commercial space taxis, currently under development by SpaceX and Boeing.
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In the 2020s, NASA astronauts also will begin flying on the agency's deep-space capsule, Orion.
"This is an exciting time to be a part of America's human space flight program," Brian Kelly, director of Flight Operations at NASA's Johnson Space Center in Houston, said in a statement.
"We encourage all qualified applicants to learn more about the opportunities for astronauts at NASA and apply," Kelly said.
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Since its selection of the famed "Mercury Seven" astronauts – Scott Carpenter, Gordon Cooper, John Glenn, Gus Grissom, Wally Schirra, Alan Shepard and Deke Slayton – in 1959, only about 300 people have been invited to join NASA's elite astronaut corps.
In addition to pilots, engineers and scientists, NASA has hired doctors and teachers.
Candidates must hold a bachelor's degree from an accredited institution in engineering, biological science, physical science or mathematics, and an advanced degree is desirable, NASA said.
Candidates also must have at least three years of related professional experience, or at least 1,000 hours of pilot-in-command time in jet aircraft. Astronaut candidates must pass the NASA long-duration spaceflight physical.
Government pay scales peg astronaut salaries between about $66,000 and $158,000 per year.