The Mercury 7: Front row, left to right, LCDR Walter Marty Schirra, USN; CAPT Donald Kent Slayton, USAF; LCOL John Herschel Glenn, Jr., USMC; LT Malcolm Scott Carpenter, USN. Back row, left to right, LCDR Alan Bartlett Shepard, Jr., USN; CAPT Virgil Ivan Grissom, USAF; CAPT Leroy Gordon Cooper, Jr., USAF. (NASA)