Since the first man in space with the soviet cosmonaut Yuri Gagarin, the NASA (National Aeronautics and Space Administration) tried to overcome the projection of the russians, with the new first project of manned space flight in the US, the Mercury Program under the leadership of Werner von Braun.
The Mercury Program has started 1958 and has ended 1963 with the last manned flight of Gordon Cooper.
Totally 25 launched have been carried out, 6 of them were manned flights and 5 of them orbital flights, one unmanned orbitalflight with with
Two major rockets have been used, the Atlas D and the Redstone spacecraft.
The first US manned spaceship was Mercury-Redstone 3-Freedom 7 with Alan Shephard, who has done 1 month after Yuri Gagarin with Wostok 1 only a ballistic flight of around 15 minutes and reaches only an altitude of around 187 km and not a full orbitflight as Yuri Gagarin.
The first US astronaut who succeeded the full orbitflight was John Glenn 1962 with Mercury-Atlas 6 Friendship 7, around 1 year after Wostok 1.
In the Mercury Program have been involved 6 manned flights and after completion this program changed over to the Geminiprogram in 1964, a spaceship as well for two astronauts and the precursor for the Apollo spaceships (Moonprogram).
At the end of the Mercury Program , Russia was until that time in front in the competition by reaching first with a manned spaceship the Moon.
Mercury 3 05.05.1961 Alan B.Shephard
first US astronaut in space (only ballistic flight)
Mercury 4 21.07.1961 Virgil I.Grissom
only ballistic flight
Mercury-Atlas 4 13.09.1961 unmanned
first US Orbitalflight, but unmanned
Mercury 6 20.02,1962 John H.Glenn
first US astronaut in spaceorbit
Mercury 7 24.05.1962 Malcolm Carpenter
Mercury 8 03.10.1962 Walter M. Schirra
Mercury 9 15.05.1963 Gordon L.Cooper