Home - Search - Browse - Alphabetic Index: 0- 1- 2- 3- 4- 5- 6- 7- 8- 9
A- B- C- D- E- F- G- H- I- J- K- L- M- N- O- P- Q- R- S- T- U- V- W- X- Y- Z
Russian gamma ray astronomy satellite. The Gamma USSR/France gamma/x-ray astronomical telescope spacecraft was derived from the Soyuz manned spacecraft and had an unusually long gestation. Astronomy, Gamma satellite, Russia. Launched 1990. Used Soyuz-Bus.

AKA: 19KA30. Status: Operational 1990. First Launch: 1990-07-11. Last Launch: 1990-07-11. Number: 1 . Gross mass: 7,350 kg (16,200 lb). Height: 7.70 m (25.20 ft). Span: 12.00 m (39.00 ft).

The basic design was first conceived in 1965 as part of a 'Cloud Space Station' - a primary space station from which a number of man-tended, free-flying spacecraft would operated. This evolved by the early 1970's into the MKBS/MOK space station complex. Various spacecraft with specialized laboratories or instrument sets would fly autonomously away from the huge N1-launched main station. Gamma was originally to be a free-flyer of this complex. The Soyuz propulsion system was used, but the descent and orbital modules were replaced by a large pressurized cylinder containing the scientific instruments.

Work on the instrument payload for Gamma began in 1972, and French participation began in 1974. However that same year the N1 launch vehicle, and the MKBS space station, were cancelled.

The Soviet space program was completely reformulated in a resolution of February 1976, which included authorization to develop the free flyer in conjunction with the DOS-7/DOS-8 space station (which would eventually evolve into Mir). The draft project for Gamma was completed in 1978, and production was authorized together with Mir on 16 February 1979. At this point Gamma included a passive docking port so that the spacecraft could be serviced by Soyuz manned spacecraft. It was planned that at six and twelve months into its one year mission Gamma would be visited by a two-crew Soyuz, who would replace film cassettes and repair or replace instruments. This approach was dropped in 1982 when it became apparent that the spacecraft was overweight and that all planned Soyuz would be needed for support of the Mir station itself. All film systems were removed and replaced with purely electronic data return methods.

By that time Gamma was scheduled originally for launch in 1984, but further severe technical delays resulted in a 1990 launch, 35 years after it was first conceived. In the end the satellite's research in the field of high-energy astrophysics, conducted jointly with France and Poland, did not produce many noteworthy results.

Gamma offered the possibility of locating COS-B sources with a precision of a few arcminutes. The mission lasted ca. 2 years.


The science instrumentation included the Gamma-1 telescope (with a Telezvezda star tracker), the Disk-M telescope, and the Pulsar X-2 telescope. All 3 instruments were mounted coaxially on the observatory, allowing for simultaneous observation of any given region of the celestial sphere.

The Gamma-1 telescope was the principle instrument aboard the Gamma observatory. It was designed to perform detailed studies in the energy range 50 MeV - 6 GeV. The system consisted of 2 scintillation counters and a gas Cerenkov counter. It had an effective area of ~2000 sq-cm. Its angular resolution at 100 MeV was 1.5 degrees. The imaging field of view was +/- 2.5 degrees. The energy resolution was 12% at 100 MeV. Rather late in the game, it was decided to include a tungsten coded aperture mask which could be moved in and out of the field of view. The mask itself was made of 2 1-D masks each having a unit cell size of 1 mm. The basic resolution achieved by the mask was ~20 arcminutes for the weakest sources (4-sigma). Shortly after launch, the power to the spark chamber failed. This resulted in the angular resolution for most of the mission being only ~ 10 degrees. The telescope was a joint Soviet-French endeavor.

The Telezvezda star tracker worked together with the Gamma-1 telescope. It had a 6 deg x 6 deg field of view, and a 5th stellar magnitude sensitivity. It had an angular resolution of 2 arcmin, making it possible to determine the Gamma-1 pointing direction to the same accuracy.

The Disk-M telescope was designed to measure fluxes in the range 20 keV - 5 MeV. The detector consisted of NaI scintillation crystals. The angular resolution of the telescope was ~ 25 arcmin. The Disk-M telescope stopped working not long after launch.

The Pulsar X-2 telescope covered 2-25 keV with ~ 30 arcmin resolution and a 10 deg x 10 deg field of view. The telescope was a joint Soviet-French endeavor.


Studies were made of the Vela pulsar, the galactic center region, the Cygnus binaries, the Heming gamma source in Taurus, and Her X-1. The observatory also gathered information about the high-energy emissions of the Sun during peak solar activity.

More at: Gamma.

Family: Astronomy, Gamma ray astronomy satellite, Space station orbit. Country: Russia. Launch Vehicles: R-7, Soyuz-U2. Launch Sites: Baikonur, Baikonur LC1. Agency: Korolev bureau, MOM. Bibliography: 102, 2, 453, 474, 6, 6515, 12479.
Photo Gallery


Credit: Manufacturer Image

1976 February 17 - .
1990 July 11 - . 10:00 GMT - . Launch Site: Baikonur. Launch Complex: Baikonur LC1. LV Family: R-7. Launch Vehicle: Soyuz-U2.

Back to top of page
Home - Search - Browse - Alphabetic Index: 0- 1- 2- 3- 4- 5- 6- 7- 8- 9
A- B- C- D- E- F- G- H- I- J- K- L- M- N- O- P- Q- R- S- T- U- V- W- X- Y- Z
© 1997-2019 Mark Wade - Contact
© / Conditions for Use