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Granat/Galactic Center
Credit: IKI/CEA


Granat and the mask of the Galaxy

GRANAT was a Russian astronomical observatory satellite dedicated to X-ray and gamma ray astronomy. GRANAT operated from 1989 to 1998 and was a collaborative observatory which included instruments from a number of European countries. The SIGMA telescope on GRANAT was a coded mask instrument provided by France. Coded-mask telescopes are a bit unusual in that they don't have imaging optics (like a lens or mirror) to produce images. Coded-mask telescopes consist of a thick patterned mask in front of the detector; from the variation of the intensity of the light falling on the detector, and from the known mask pattern, an image of the observed object can be reconstructed. A SIGMA image of the galactic center is shown above. This image is one of the deepest high energy images of the galactic center ever obtained.


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Each week the HEASARC brings you new, exciting and beautiful images from X-ray and Gamma ray astronomy. Check back each week and be sure to check out the HEAPOW archive!


Page Author: Dr. Michael F. Corcoran
Last modified April 30, 2001