http://phys.org/news/2015-09-converging-black-holes-virgo-constellation.html?utm_source=nwletter&utm_medium=email&utm_content=splt-item&utm_campaign=daily-nwletter
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A supermassive black hole about to cannibalize its own can be detected by the mysterious flickering of a quasar—the beacon of light produced by black holes as they burn through gas and dust swirling around them. Normally, quasars brighten and dim randomly, but when two black holes are on the verge of uniting, the quasar appears to flicker at regular intervals, like a light bulb on timer......
Read more at: http://phys.org/news/2015-09-converging-black-holes-virgo-constellation.html#jCp
