The Granat Satellite

GRANAT was a Russian dedicated X-ray/gamma ray astronomy mission in collaboration with other European countries. Launched on 1 December 1989, Granat operated for almost 9 years. After an initial period of pointed observations, Granat went into survey mode in September 1994.

Mission Characteristics

• Coded-mask X-ray telescope (SIGMA)
  0.03-1.3 MeV, eff. area 800 cm², FOV 5°x5°
• Coded-mask X-ray telescope (ART-P)
  4-60 keV, eff. area 1250 cm², FOV 1.8°x1.8°
• X-ray proportional counter spectrometer (ART-S)
  3-100 keV, eff. area 2400 cm² at 10 keV, FOV 2°x2°
• All-sky monitor (WATCH)
  6-120 keV, eff. area 45 cm², FOV All-sky
• Gamma-ray burst experiment (PHEBUS)
  0.1-100 MeV, 6 units of 100 cm² each, FOV All-sky
• Gamma-ray burst experiment (KONUS-B)
  0.02-8 MeV, 7 units of 315 cm² each, FOV All-sky
• Gamma-ray burst experiment (TOURNESOL)
  0.002-20 MeV), FOV 5°x5°

• A very deep (more than 5 million sec.) imaging of the galactic center region.
• Discovery of electron-positron annihilation lines from the Galactic "micro-quasar" 1E1740-294 and the X-ray Nova Muscae.
• Study of spectra and time variability of black hole candidates.