Because the absorbing material was in between the Earth and the black hole, the matter must be falling into the black hole. The galaxy NGC 3516 is moving away from the earth, producing a slight red-shift in its emission. The bit of matter that Nandra interpreted as falling into the black hole had a much greater red-shift than the galaxy, produced by the high speeds it attained before falling into the black hole void. We know from general physical arguments that the active galaxies are powered by accretion, but no one's ever seen it. There's a possibility that these data indicate that we are actually starting to see direct evidence for accretion.
Accretion occurs when a black hole bites off more than it can chew.
Friction within this disk causes it to shine brightly, forming a warning beacon for the invisible black hole lurking in the center. Nandra is with the Universities Space Research Association. Other scientists involved in the observation include Ian George, Jane Turner and Tahir Yaqoob, all of whom appear on the Astrophysical Journal Letters paper. Explore the net ASCA Information - learn more about the Advanced Satellite for Cosmology and Astrophysics. Subscriptions Subscribe to Astronomy Now and have Britain's best selling astronomy magazine delivered to your door every month.