Apollo–Soyuz Test Project made the Soviet Union's policy of détente official in his 1956 doctrine of peaceful coexistence at the 20th Congress of the Communist Party of the Soviet Union, the two nations seemed to be in perpetual conflict. Due to tense relations, space cooperation between the United States and the Soviet Union was unlikely in the early 1970s. On June 7, 1971, the USSR had launched the first piloted orbital space station, Salyut 1. Meanwhile, the United States had launched the Apollo 14 mission several months prior, the third spacecraft to land humans on the moon. Each side gave the other little
NASA a flight around the Moon in December 1968. Shortly before, the Soviets had sent an unmanned spacecraft around the Moon. On the next two missions docking maneuvers that were needed for the Moon landing were practiced and then finally the Moon landing was made on the Apollo 11 mission in July 1969. The first person to stand on the Moon was Neil Armstrong, who was followed by Buzz Aldrin, while Michael Collins orbited above. Five subsequent Apollo missions also landed astronauts on the Moon, the last in December 1972. Throughout these six Apollo spaceflights, twelve men walked on the Moon.