Swift survey finds 'missing' active galaxies
Friday, January 21, 2011 - 15:30
in Astronomy & Space
Seen in X-rays, the entire sky is aglow. Even far away from bright sources, X-rays originating from beyond our galaxy provide a steady glow in every direction. Astronomers have long suspected that the chief contributors to this cosmic X-ray background were dust-swaddled black holes at the centres of active galaxies. The trouble was, too few of them were detected to do the job...
