Soyuz 17

This article is about the 1975 mission. For the mission identified by NASA as ISS Soyuz 17, see Soyuz TMA-13.

Soyuz 17

Mission duration	29 days, 13 hours, 19 minutes, 45 seconds
Orbits completed	479
Spacecraft properties
Spacecraft type	Soyuz 7K-T
Manufacturer	NPO Energia
Launch mass	6,800 kilograms (15,000 lb)
Crew
Crew size	2
Members	Aleksei Gubarev Georgi Grechko
Callsign	Зенит (Zenit - "Zenith")
Start of mission
Launch date	January 10, 1975, 21:43:37 (1975-01-10UTC21:43:37Z) UTC
Rocket	Soyuz
Launch site	Baikonur 1/5
End of mission
Landing date	February 9, 1975, 11:03:22 (1975-02-09UTC11:03:23Z) UTC
Landing site	110 kilometres (68 mi) NE of Tselinograd
Orbital parameters
Reference system	Geocentric
Regime	Low Earth
Perigee	185 kilometres (115 mi)
Apogee	249 kilometres (155 mi)
Inclination	51.6 degrees
Period	88.8 minutes
Docking with Salyut 4
---- Soyuz programme (Manned missions) ← Soyuz 16 Unnumbered →

Soyuz 17 (Russian: Союз 17, Union 17) was the first of two long-duration missions to the Soviet Union's Salyut 4 space station in 1975. The flight set a Soviet mission-duration record of 29 days, surpassing the 23-day record set by the ill-fated Soyuz 11 crew aboard Salyut 1 in 1971.

Crew

Position	Cosmonaut
Commander	Aleksei Gubarev First spaceflight
Flight Engineer	Georgi Grechko First spaceflight

Backup crew

Position	Cosmonaut
Commander	Vasili Lazarev
Flight Engineer	Oleg Makarov

Reserve crew

Position	Cosmonaut
Commander	Pyotr Klimuk
Flight Engineer	Vitali Sevastyanov

Mission parameters

• Mass: 6,800 kg (15,000 lb)
• Perigee: 185 km (115 mi)
• Apogee: 249 km (155 mi)
• Inclination: 51.6°
• Period: 88.8 min

Mission highlights

Salyut 4 was launched 26 December 1974, and Soyuz 17, with cosmonauts Georgi Grechko and Aleksei Gubarev as its first crew, was launched 16 days later on 10 January 1975. Gubarev manually docked Soyuz 17 to the station on 12 January, and upon entering the new station he and Grechko found a note from its builders which said, "Wipe your feet!"

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 worked between 15 and 20 hours a day, including their 2​¹⁄₂ hour exercise period. One of their activities included testing communication equipment for tracking ships and contacting mission control via a Molniya satellite.

Astrophysics was a major component of the mission, with the station's solar telescope activated on 16 January. The crew later discovered that the main mirror of the telescope had been ruined by direct exposure to sunlight when the pointing system failed. They resurfaced the mirror on 3 February and worked out a way of pointing the telescope using a stethoscope, stopwatch, and the noises the moving mirror made in its casing.

On 14 January, a ventilation hose was set up from Salyut 4 to keep the Soyuz ventilated while its systems were shut down. On 19 January 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 cosmonauts began powering down the station on 7 February and they returned to Earth in the Soyuz capsule two days later. They safely landed near Tselinograd in a snowstorm with winds of 72 km/h and wore gravity suits to ease the effects of re-adaptation.