Mercury 7 astronauts trying out the Mercury space capsule mock-up. Project Mercury was the first human spaceflight programme of the United States. It ran from 1959 to 1963, succeeding in putting the first US astronaut in space on 5 May 1961. The small Mercury spacecraft was only large enough for one crew member. A total of six manned Mercury missions were flown, with flights launched from Cape Canaveral Air Force Station in Florida, USA. The Mercury astronauts were Alan B. Shepard, Walter M. Schirra, John H. Glenn, Virgil I. Grissom, M. Scott Carpenter, Donald Slayton, and L. Gordon Cooper.