Salyut 4
Expedition 1

Launch from the Baikonur Cosmodrome; landing 110 km northeast of Tselinograd.

Following a one day solo flight Soyuz 17 docked with the space station Salyut 4 on January 12, 1975, which had been launched three days earlier.

Salyut 4 was in an unusually high circular orbit of 350 km (220 mi) when Soyuz 17 docked with the station. Salyut designer Konstantin Feoktistov said this was to ensure propellant consumption would be half of what was needed for lower-altitude Salyuts.

The crew transfered into space station and stayed there 29 days. The crew worked between 15 and 20 hours a day, including their 21/2 hour exercise period. One of their activities included testing communication equipment for tracking ships and contacting mission control via a Molniya satellite.

Several astronomical experiments were performed. The crew discovered that the main mirror of the solar telescope had been ruined by direct exposure to sunlight when the pointing system failed. They resurfaced the mirror and worked out a way of pointing the telescope using a stethoscope, stopwatch, and the noises the moving mirror made in its casing.

On January 14, 1975, a ventilation hose was set up from Salyut 4 to keep the Soyuz ventilated while its systems were shut down. On January 19, 1975 it was announced that ion sensors were being used to orient the station, a system described as being more efficient.

A new teleprinter was used for communications from the ground crew, freeing the Salyut crew from constant interruptions during their work.

The landing occured in a snowstorm with winds of 72 km/h.