Counting up the Active Black Holes with Chandra

[Fraser]

The newest image released from NASA's Chandra X-Ray Observatory is helping astronomers build up a census of the number of actively feeding supermassive black holes across the Universe. ...

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[Grand_Lunar]

I wonder if the census will list the mass of each black hole.

I also wonder if this might help in figuring if the universe will be "open" or "closed".

[max8166]

Scientists are hoping to build up a comprehensive picture of where (and thus when), these black holes were blasting out radiation.

Ummm... I thought that the definition of a black hole was that it doesn't "Blast Out" any radiation. (nothing escapes) Maybe I Am reading this wrong?

[antoniseb]

Ummm... I thought that the definition of a black hole was that it doesn't "Blast Out" any radiation. (nothing escapes) Maybe I Am reading this wrong?

No you aren't reading it wrong. The radiation is being blasted out by the energy created by colliding particles that are moving at nearly the speed of light because they fallen almost into a black hole. Note that in addition to powerful gravity, there is also some extreme magnetism affecting the motion of the charged particles as well. So the singularity is not blasting out the radiation, but the space around it is, and as a short-hand we describe that whole environment as 'the black hole'.