Manage episode 227151794 series 96788
Sagittarius A*. This image was taken with NASA's Chandra X-Ray Observatory. Ellipses indicate light echoes. Full-field is 12.5 arcmin across. original source
NASA - Part of File:Gcle.jpg
Created: 23 July 2014
Significantly Modest Singularity (Black Hole). Ken Croswell Ken Croswell, @NewScientist
"...Black holes come in two main weight classes. Stellar-mass black holes form when a large star collapses, and are roughly ten times the mass of the sun. In contrast, supermassive black holes, such as Sagittarius A* at the Milky Way’s centre, typically have millions or billions of solar masses.
And black holes in between? Good luck finding one: most claims for their existence have diminished in the light of new evidence.
Now, Bülent Kızıltan of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, and his colleagues have used a new technique to uncover an intermediate-mass black hole. It’s at the centre of the bright globular cluster 47 Tucanae, which is 15,000 light years from Earth. The cluster’s many stars radiate a combined luminosity 500,000 times more than the sun’s and have a total mass 700,000 times greater...."
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