Salyut 5

Salyut 5 was the public name for OPS-3, the third and final Almaz military station placed in orbit. NASA's Russian space station history lists it among the first-generation military Salyut stations, while Spacefacts records Soyuz 21 as its first resident crew. The station supported reconnaissance-oriented operations, biomedical and engineering experiments, and later hosted Soyuz 24 after the Soyuz 23 docking attempt failed.