While Armstrong and Aldrin walked the Moon, a Soviet probe crashed nearby
Three days before Apollo 11 launched, the Soviet Union sent an uncrewed probe, Luna 15, to scoop up lunar soil and beat the Americans home with it. It reached orbit first. On July 21, 1969, with Armstrong and Aldrin still on the surface, it malfunctioned during descent and crashed into Mare Crisium.
The race had begun with a Soviet shock. Sputnik 1 in October 1957 suggested Moscow could deliver weapons across continents, and Yuri Gagarin's orbital flight in April 1961 put the USSR ahead again. Because Soviet rockets could lift more, President John F. Kennedy picked a target beyond anyone's existing hardware, so both sides would start level. In May 1961 he told Congress the nation should put an astronaut on the Moon, and bring him home alive, within the decade. Not everyone was sold: the MIT mathematician Norbert Wiener mocked it as a moondoggle, and Kennedy twice proposed a joint mission with the Soviets, an idea dropped after his death.
Engineering choices made it feasible. In July 1962 NASA chose lunar orbit rendezvous, allowing a single Saturn V to carry a three-part spacecraft: a command module, a service module and a two-stage lunar lander. Silicon integrated circuits went into the Apollo Guidance Computer. The fire that killed Gus Grissom, Ed White and Roger Chaffee in January 1967 halted the programme, but four test flights in 1968 and 1969, including a full rehearsal in lunar orbit by Apollo 10, cleared the way.
The crew came together partly by accident. Crew swaps between Apollo 8 and 9 lined Neil Armstrong up for command of Apollo 11. Michael Collins lost his Apollo 8 seat when surgery was needed on a bony growth in his spine, then joined Armstrong's crew after recovering. Deke Slayton even offered to replace Buzz Aldrin with Jim Lovell; Armstrong slept on it and declined, feeling Lovell deserved his own command, which turned out to be Apollo 13.
Launched on July 16, the lander Eagle touched down in the Sea of Tranquility on July 20 while Collins orbited in Columbia. About six hours later Armstrong stepped out before an estimated 600 million television viewers, with Aldrin following nineteen minutes after. They collected 21.5 kilograms of material, which yielded three minerals previously unknown, and splashed down in the Pacific on July 24. Columbia now sits in the National Air and Space Museum; Eagle's descent stage never left the Moon.
Source: Apollo 11
