It means more than 11000 imaging
hours out of which more than 2000 hours dedicated to the Galactic Center.
Since december 1, 1989, the SIGMA
telescope has been making more than 800 sky observation sessions achieving
spectrometry as well as high resolution images (a few arc-minutes accuracy) of
galactic and extragalactic sources between 35 keV and 1.3 MeV.
It means more than 11000 imaging
hours out of which more than 2000 hours dedicated to the Galactic Center.
The SIGMA planning gives the list
of the observations made by the telescope for several years :
Years 1989 and
1990