Gamma (satellite)

Gamma
General information
Organization RKA
Launch date 11 July 1990[1]
Mission length 2 years[1]
Orbit height 375 km[1]
Location Earth orbit
Wavelength Gamma ray
Instruments
Gamma-1 telescope 50 MeV to 6 GeV[1]
Disk-M telescope 20 keV to 5 MeV[1]
Pulsar X-2 telescope 2-25 keV[1]
References: [1]

Gamma was a Soviet gamma ray telescope. It was launched on 11 July 1990 into an orbit around Earth with a height of 375 km and an inclination of 51.6 degrees. It lasted for around 2 years. On board the mission were three telescopes, all of which could be pointed at the same source. The project was a joint Soviet-French project.[1]

Contents

Background

The Gamma-1 telescope was the main telescope. It consisted of 2 scintillation counters and a gas Cerenkov counter. With an effective area of around 0.2 square metres (2.2 sq ft), it operated in the energy range of 50 MeV to 6 GeV. At 100 MeV it initially had an angular resolution of 1.5 degrees, with a field of view of 5 degrees and an energy resolution of 12%. A Telezvezda star tracker increased the pointing position accuracy of the Gamma-1 telescope to 2 arcminutes by tracking stars up to an apparent magnitude of 5 within its 6 by 6 degree field of view. However, due to the failure of power to a spark chamber, for most of the mission the resolution was around 10 degrees.[1]

The telescope was conceived in 1965, as part of a Cloud Space Station. Work on Gamma began in 1972, and it became a joint venture with France in 1974. However, also in 1974, the MKBS/MOK space station complex (as the Cloud Space Station had evolved into by then) was cancelled. A few years later, in February 1976, the Soviet space program was reconfigured, and on 16 February 1979 production of the telescope was authorized. The telescope was originally planned to be launched in 1984, but technical delays pushed the launch back to 1990.[2]

Operation

The Disk-M telescope operated in the energy range 20 keV - 5 MeV. It consisted of Sodium iodide scintillation crystals, and had an angular resolution of 25 arcminutes. However, it stopped working shortly after the mission was launched.[1]

Finally, the Pulsar X-2 telescope had 30 arcminute resolution and a 10 deg x 10 deg field of view, and operated in the energy range 2-25 keV.[1]

Observations included studies of the Vela Pulsar, the Galactic Centre, Cygnus X-1, Hercules X-1 and the Crab Nebula. The telescopes also measured the Sun during peak solar activity.[1]

References

External links