Soyuz 20
# Soyuz 20

Soyuz 20 (Russian: Союз 20, Union 20) was an uncrewed spacecraft launched by the Soviet Union. It was a long-duration test of the Soyuz spacecraft that docked with the Salyut 4 space station. Soyuz 20 performed comprehensive checking of improved on-board systems of the spacecraft under various flight conditions. It also carried a biological payload. Living organisms were exposed to three months in space.

## Mission parameters

* Mass: 6,570 kg (14,480 lb)
* Perigee: 199.7 km (124.1 mi)
* Apogee: 263.5 km (163.7 mi)
* Inclination: 51.6°
* Period: 88.8 minutes

## Return

It was recovered on 16 February 1976 at 02:24 UTC.

