Astronaut Donald Slayton, cosmonaut Aleksey Leonov and astronaut Thomas Stafford are photographed in the Soviet Soyuz Orbital Module during the Apollo-Soyuz test project docking in Earth orbit mission, July 1975.AP
The Apollo–Soyuz Test Project was the first U.S.-Soviet cooperative mission in space. The project was launched on July 15, 1975. The mission involved docking an Apollo Command/Service Module on the Soviet Soyuz 19, as well as scientific investigations. The Apollo-Soyuz crew included three American astronauts: "Deke" Slayton, Tom Stafford, and Vance Brand - as well as two Russian cosmonauts: Aleksey Leonov and Valeriy Kubasov.
The Apollo-Soyuz project marked the end of the Space Race that began in 1957 with the Sputnik launch.