[Post reconstruction in progress after 25.10.07 hack (body, comments and images to follow)]:
There’s been a recent discovery* of an unusual black hole. It is about sixteen times the mass of our sun. While this might not seem as dramatic as the black holes that are millions of times the mass of our sun that live at the cores of galaxies, such large black holes that result from the collapse of ordinary stars have hitherto been unknown. This presents an important and exciting puzzle about the processes by which black holes form from the collapse of stars. There’s evidently more going on than previously thought, possibly as a result of complicated interactions with its companion star during formation.
(Image: A Harvard-Smithsonian Center image of the galaxy Messier 33, in which the new black hole was found.)
I talk a bit more about this on Correlations, and you can read more about the recent announcement of this work by the team of researchers (a team led by Jerome Orosz of San Diego State University) in this space.com article, this this AFP article (via Yahoo News), and especially this press release from the Chandra X-ray Observatory. The paper on the work came out in Nature today.