The Apollo program was the successful conclusion of the U.S. effort to achieve, within the decade, the goalÑset by President
John F. Kennedy on May 25, 1961Ñof
landing a man on the Moon and returning him safely to Earth. It followed the Gemini manned-flight
program conducted in 1966-67 to develop the necessary techniques of orbiting, docking, and extravehicular activity (EVA). The main elements of the Apollo project were the three-man Apollo spacecraft; the two-man Lunar Excursion Module (LEM), or Lunar Module (LM); and the Saturn family of rockets, consisting of the Saturn 1, the Saturn 1B, and the Saturn 5. These units made up the first manned, interplanetary transportation system. Using this system, astronauts landed on the Moon, where they explored and collected samples at six sites on the near side between July 1969 and the end of December 1972. The total cost of developing and operating the Apollo-Saturn transportation system in the lunar program was $25 billion.Between October 1968, when the Apollo-Saturn transportation system underwent its first full space test, and July 1975, when it was used for the last time, the National Aeronautics and Space Administration (NASA) launched 15 manned Apollo-Saturn flights. Eleven of these were missions in the lunar landing program, including two test flights in low Earth orbit, two test flights in lunar orbit, six landings, and one circumlunar flight, during which the planned landing was aborted. During the testing period three fatalities occurred on the launchpad at the Kennedy Space Center, Florida, but none in actual flight.After completion of the lunar landing program, four flights were carried out: three were missions that ferried astronauts to and from the Skylab experimental space station in 1973-74, and one was a joint flight with Soviet cosmonauts in the Apollo-Soyuz Test Project in 1975.