In 1958, Glenn joined Project Mercury. He was the oldest of the seven pilots selected. Although Alan Shepard and Gus Grissom flew in outer space before Glenn did, Glenn was the first American to orbit the earth, as neither of the previous two had made a full orbit. He flew a Mercury spacecraft called Friendship 7. His first words when reaching orbit were "Zero G and I feel fine." He retired from NASA and the military after his flight.