News tagged with active galaxies

What activates a supermassive black hole?

A new study combining data from ESO's Very Large Telescope and ESA's XMM-Newton X-ray space observatory has turned up a surprise. Most of the huge black holes in the centres of galaxies in the past 11 billion years were not ...

dateJul 13, 2011 in Astronomy
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How often do giant black holes become hyperactive?

(PhysOrg.com) -- A new study from NASA's Chandra X-ray Observatory tells scientists how often the biggest black holes have been active over the last few billion years. This discovery clarifies how supermassive black holes ...

dateDec 20, 2010 in Astronomy
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