NASA's original Mercury Seven astronauts were the best of the best.

NASA’s original Mercury Seven astronauts were the best of the best. The requirements: military test pilots between 25 and 40 years old, in exceptional health, and no taller than 5 feet, 11 inches because of the size of the capsule.

All but one flew in Project Mercury, the single-seaters. Three went on to fly in Gemini aboard two-man capsules. One, Wally Schirra, flew in all three of NASA’s pioneering programs — Mercury, Gemini and Apollo. Another walked on the moon.

The seven in the order they flew:

Alan Shepard: May 5, 1961. Suborbital flight aboard Freedom 7. Grounded by inner-ear ailment, which eventually was corrected. Fifth man to walk on moon, as Apollo 14 commander in 1971. Died in 1998 at age 74. Navy.

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Gus Grissom: July 21, 1961. Suborbital flight aboard Liberty Bell 7. Flew during Gemini. Killed in Apollo 1 spacecraft fire on launchpad in 1967 at age 40. Air Force.

John Glenn: Feb. 20, 1962. Orbital flight aboard Friendship 7. World’s oldest spaceman, flying at age 77 aboard space shuttle Discovery in 1998. Now 90 and living in Columbus, Ohio. Marines.

Scott Carpenter: May 24, 1962. Orbital flight aboard Aurora 7. Now 86 and living in Florida and Colorado. Navy.

Wally Schirra: Oct. 3, 1962. Orbital flight aboard Sigma 7. Flew in Gemini and Apollo. Died in 2007 at age 84. Navy.

Gordon Cooper: May 15-16, 1963. Orbital flight aboard Faith 7. Flew in Gemini. Died in 2004 at age 77. Air Force.

Deke Slayton: Grounded in 1962 by a heart condition. Flew on Apollo-Soyuz mission in 1975, orbital linkup of U.S. and Soviet spacecraft. Died in 1993 at age 69. Air Force.