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Illustration of the Salyut 4 space station.

Illustration of the Salyut 4 space station. (Credit: Soviet Space Program)

Lifetime: December 1974 - February 1977

Country (primary): Soviet Union

Primary Science

Salyut-4 was the fourth space station of the Soviet Salyut series. The Salyut space stations were aimed at conducting long-term research into the challenges of living in space. In addition, the stations carried a variety of astronomical and biological experiments.

High Energy Science

Salyut-4 carried an X-ray telescope to study cosmic X-ray sources.

Science Highlights

  • Detected highly variable, low-energy flux (0.6-0.9 keV) in Scorpius X-1
  • Non-detection of Circinus X-1 provided an upper limit on its 0.2-2.0 keV emission
  • Monitored Cygnus X-1 and observed highly variable flux over time and energy

Links to more information


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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