Following on the heels of Shepard’s flight, President John F. Kennedy (1917-1963) made a dramatic announcement to Congress on 25 May 1961. He called for the achievement of landing a man on the moon and returning him safely to the Earth before the end of the decade. Kennedy’s announcement accelerated the space race because it gave an increased sense of national importance and urgency to NASA. The agency continued with Project Mercury, but it accelerated development of its
Astronaut Buzz Aldrin stands on lunar surface near lunar module facing the American flag in 1969.
Lunar landing program, Project Apollo. In December of 1961, NASA announced Project Gemini, which would place two men into Earth orbit for extended periods. Gemini would practice many of the techniques used on Apollo, including the rendezvous of two spacecraft, the docking of two spacecraft, and spacewalking.
NASA successfully launched astronaut John H. Glenn Jr. into orbit on 20 February 1962, in the Mercury spacecraft, Friendship 7. This flight required much more effort on the part of the astronaut, the flight controllers, and the spacecraft, which had to perform critical maneuvers and keep the astronaut alive for several hours. The Mercury program continued with three more flights, concluding with Gordon Cooper’s successful 22-orbit flight on 15 May 1963. Mercury achieved its major objectives of placing a man into Earth orbit and recovering him successfully.
NASA announced Lunar Orbit Rendezvous (LOR) as the Apollo mission mode in June of 1962. With LOR, von Braun’s Saturn V rocket, with a thrust of 7,500,000 pounds, would propel a crew spacecraft, a service module with supplies, and a lunar module toward the moon. Once in orbit around the moon, the lunar module would separate from the command and service modules, carrying two astronauts to the moon’s surface while the command module pilot stayed in lunar orbit. The lunar module itself would have two stages, an ascent stage and a descent stage. When the astronauts finished their exploration of the moon’s surface, they would return to lunar orbit in the ascent stage, leaving the descent stage on the moon, and dock with the command module. On approach to Earth, both the ascent stage and the service module would be jettisoned. Only the command module would return to Earth. Although NASA originally thought this method too risky, its weight-saving advantages and the fact that each component could be engineered independently for a particular purpose ultimately made it the most practical of the modes considered. The LOR mission mode determined nearly every aspect of Apollo development, from crew training to spacecraft design to spacecraft maneuvering systems.
Mercury astronaut Gus Grissom and “New Nine” astronaut John Young piloted the first flight of Project Gemini, on 23 March 1965. The Gemini spacecraft, while based on the Mercury spacecraft, was larger and had a number of more sophisticated systems to allow performance in maneuvering, rendezvous, and docking. Later Gemini flights would dock with the Agena target vehicle, which was really the hollowed-out upper stage of an Atlas rocket fitted with docking adapters. But on 18 March 1965, Korolev dealt the United States another blow when Aleksei Leonov made the first spacewalk, lasting twelve minutes and nine seconds. Leonov and fellow cosmonaut Pavel Belyayev orbited the Earth in Voshkod 2, an updated version of Gagarin’s Vostok spacecraft. Edward H. White III of Gemini IV performed the first American spacewalk on 3 June 1965. However, from this point on, American performance in manned spaceflight would consistently outstrip Soviet performance up to the lunar landings.
Between March 1965 and November 1966, ten Gemini flights took place. While the United States set one space record after another, no cosmonauts orbited the Earth. Gemini VI rendezvoued with Gemini VII in October of 1965, with the crew of Gemini VII spending two weeks in Earth orbit. The first successful docking of two spacecraft occurred during Gemini VIII, which was crewed by Neil Armstrong and David Scott. The final flight of the program, Gemini XII, solved many problems inherent to spacewalking and helped to refine flying techniques as well as spacesuit technology. With the conclusion of Project Gemini, spaceflight had become operational if not routine, and many of the skills needed for Apollo had been honed to sharp accuracy.