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Apollo-Soyuz Test Project

Apollo-Soyuz Test Project

The Apollo capsule ready to dock with Soyuz.

The Apollo capsule ready to dock with Soyuz. (Credit: Soyuz crew)

The Soyuz capsule ready to dock with Apollo.

The Soyuz capsule ready to dock with Apollo. (Credit: Apollo crew)

Apollo astronaut and Soyuz cosmonaut shake hands in space

Astronaut Thomas P. Stafford (in foreground) and cosmonaut Aleksei A. Leonov make a historic handshake during the Apollo Soyuz Test Project docking mission in Earth oribt. (Credit: NASA)

The Apollo-Soyuz Test Project, or ASTP for short, was the first international manned spaceflight. It was designed to test the compatibility of rendezvous and docking systems for American and Soviet spacecraft, to open the way for international space rescue as well as future joint manned flights.

Lifetime: July 1975 (Launch of Apollo) - July 24, 1975 (splashdown of Apollo)

Country (primary): United States and Soviet Union

Primary Science

The Apollo-Soyuz Test Project included joint and separate scientific experiments for both crews. The primary mission for the project was that of international cooperation and testing the compatilibity of docking the American and Soviet spacecraft together. Additional science included extereme ultraviolet astronomy and an artificial solar eclipse to allow imaging of the solar corona.

Science Highlights

  • Detection of extreme ultraviolet sources outside the solar system.
  • Discovery of X-ray emission from supernova remnant MSH 14-63.
  • Disocvery of pulsations from SMC X-1.

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A service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA/GSFC

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