The Apollo Program was the third United States manned spaceflight program, following the Mercury program and the Gemini program. Apollo was originally conceived late in the Eisenhower? administration as a follow-on to Mercury for advanced earth-orbital missions. It was dramatically reoriented to an aggressive lunar landing goal by President Kennedy, announced at a special joint session of Congress on May 25, 1961:
The Apollo program included eleven manned flights, designated Apollo 7 thru Apollo 17, all launched from the KSC. Apollo 2 thru Apollo 6 were unmanned test flights; the Apollo 1 designation was applied to the originally planned first manned flight which ended in a disastrous fire during a launch pad test that killed three astronauts. The first of the manned flights employed the Saturn 1-B launch vehicle, the following flights all used the more powerful [Saturn V]?. Two of the flights (Apollo 7 and Apollo 9) were earth orbital missions, two of the flights (Apollo 8 and Apollo 10) were lunar orbital missions, and the remaining 7 flights were lunar landing missions (although one, Apollo 13, failed to land).
Briefly, Apollo 7 tested the Apollo command and service modules (CSM) in earth orbit. Apollo 8 tested the CSM in lunar orbit. Apollo 9 tested the lunar module (LM) in earth orbit. Apollo 10 tested the LM in lunar orbit. Apollo 11 achieved the first manned lunar landing. Apollo 12 achieved the first lunar landing at a precise location. Apollo 13 failed to achieve a lunar landing, but succeeded in returning the crew safely to earth following a potentially disastrous in-flight explosion. Apollo 14 resumed the lunar exploration program. Apollo 15 introduced a new level of lunar exploration capability, with a long-stay-time LM and a lunar roving vehicle. Apollo 16 was the first manned landing in the lunar highlands. Apollo 17, the final mission, was the first to include a scientist-astronaut.
Originally three additional lunar landing missions had been planned, as Apollo 18 thru Apollo 20. These missions were cancelled to make funds available for the development of the Space Shuttle, and to make their Apollo spacecraft and Saturn V launch vehicles available to the [Skylab program]?. Only one of the Saturn Vs was actually used; the others became museum exhibits.
The Apollo program was at least partly motivated by psycho-political considerations, in response to persistent perceptions of American inferiority in space technology vis-a-vis the Soviets, in the context of the Cold War. In this respect it succeeded brilliantly. In fact, American superiority in manned spaceflight was achieved in the precursory Gemini program, even before the first Apollo flight.
Many astronauts and cosmonaut?s have commented on the profound effects that seeing earth from space has had on them. One of the most important legacies of the Apollo program was the now-common, but not universal view of the Earth as a fragile, small planet, captured in the photographs taken by the astronauts during the lunar missions. These photographs have also motivated many people toward environmentalism.
The name Apollo refers to the Greek god.
Official Apollo program website: http://spaceflight.nasa.gov/history/apollo/index.html