Project Mercury -- America's first Man-in-Space program, one-man capsules (1961-1963). The first two manned flights were suborbitals while the remaining 4 were flights of 3 to 22 orbits.
- Mercury-Redstone 3, Freedom 7, Alan Shepard, Jr., 5/5/61, 15 minutes in space, first American in space.
- Mercury-Redstone 4, Liberty Bell 7, Virgil Grissom, 7/21/61, Also a suborbital flight of 15 minutes. Spacecraft sank.
- Mercury-Atlas 6, Friendship 7, John H. Glenn, Jr. 2/20/62, 4 hours 55 minutes, 3 orbits, first American in orbit.
- Mercury-Atlas 7, Aurora 7, Scott Carpenter, 5/24/62, a repeat of Glenn's flight, except Carpenter overshot the landing by 250 miles.
- Mercury-Atlas 8, Sigma 7, Walter Schirra, 10/3/62, 6 orbits, 9h 13m.
- Mercury-Atlas 9, Faith 7, L. Gordon Cooper, 5/15-16/63, 22 orbits, 34h 19m.
One additional Mercury astronaut, "Deke" Slayton, did not fly in this program due to a heart irregularity.
The Mercury capsule has been described as appearing like a television picture tube. It is conical, with a rounded bottom 74" in diameter,and a short cylinder in place of a peak, total length of 114 inches. The round bottom is the heat shield protecting the single astronaut during re-entry. The astronaut sits (actually, lies) with his back to the shield. The capsule in orbit weighed between 3100 and 3900 pounds depending on payload.