BANGALORE: The first astronomer's telegram (Atel no. 8185) from the Scanning Sky Monitor (SSM) observations on-board Astrosat - India's first astronomy satellite - has been received by ISRO.
The SSM was pointed to "GRS 1915+105", an X-ray binary star system which features a regular star and a black hole, and caught it exhibiting the 'beta' class of variability on October 14, one of the many types of variability this source exhibits, some of which are associated with its spectral states.
"On October 15, the Soft X-ray Telescope (SXT) door was opened successfully and it will observe the sky after 10 days," ISRO has said.
Earlier in the month on October 9, Astrosat spotted the Crab Nebula using the Cadmium Zinc Telluride Imager (CZTI) instrument. The Crab Nebula is the brightest hard X-ray source in the sky.
ISRO officials described the sighting of the Crab as significant and said that this furthers ISRO's chances of other celestial X-ray sources, aiding researchers. Astrosat has also spotted and viewed Cygnus X-1, a black hole source and now, the High voltage of Near UV, Visible channel and Far UV channel of the UV Imaging telescope (UVIT) has been switched on and detectors have been tested with low gain and found satisfactory and put back in off condition.
