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
Apollo 21 Apollo 21 "Apollo 21" is an apocryphal reference to an eleventh manned Moon landing mission of NASA's Apollo program. Apollo contracted for the construction of fifteen Saturn V launch vehicles used to launch the Apollo spacecraft to the Moon, and achieved the first manned landing with the sixth one (Apollo 11), leaving nine for follow-on lunar missions, through Apollo 20. However, budget cuts caused NASA to cancel the last three missions, ending the lunar program after Apollo 17. One Saturn V was used to launch the Skylab space station, and parts of the other two became museum displays. An "Apollo