http://www.nbcnews.com/science/black-hole-one-incredibly-bright-2D11665030
November 27, 2013 - NBC News
A black-hole system in a neighboring galaxy is twice as bright as astronomers had thought possible, a new study reports.
...
The research team, led by Jifeng Liu of the Chinese Academy of Sciences
in Beijing, studied ULX-1 using the Gemini Observatory in Hawaii and
two NASA spacecraft, the Hubble Space Telescope and the Chandra X-ray Observatory.
...