From an interesting article in Science Magazine – Trio of big black holes spotted in galaxy smashup, one sentence jumped out at me…
…three supermassive black holes orbiting close to one another, two of them just a few hundred light-years apart.
Golly – JUST a few hundred light-years apart.
Otherwise the item is interesting because this would be a great source of gravitational waves. Harnessing a small or quantum singularity and vibrating that may be more useful, but until we figure that out, we can watch these supermassive babies.
Ref:
http://news.sciencemag.org/physics/2014/06/trio-big-black-holes-spotted-galaxy-smashup
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