History: NASA Archive Photography

- Apollo-Soyuz Test Project (1975–1981)
In the 1970s the cold war was thawing and as a consequence the Apollo-Soyuz Test Project (ASTP) was introduced. It was the first joint flight of the U.S. and Soviet space programs. The mission took place in July 1975. For the United States, it was the last Apollo flight, as well as the last manned space launch until the flight of the first Space Shuttle in April 1981. Manned Skylab and ASTP missions used the smaller Saturn IB with Apollo CSM, not the Saturn V.
The mission included both joint and separate scientific experiments, and provided useful engineering experience for future joint US–Russian space flights, such as the Shuttle–Mir Program and the International Space Station.