Andromeda Galaxy Photobombed by Supermassive Black Hole

 A research team using data from the Chandra X-ray Observatory with additional data from the Gemini North telescope in Hawaii has discovered that a binary star system that was thought to be a part of the Andromeda galaxy is in fact 1,000 times more distant than previously thought. Further research has shown that J0045+41 is in fact not stars, but a pair of giant black holes.
 Astronomers believe that the black hole binary system is located about 2.6 billion light-years from Earth. In comparison, if researchers are correct, the separation between the two giant black holes may only be a 1/100th of a light-year apart. This would correspond to only about a few hundred times the distance between our Earth and the Sun.
 According to a statement from Chandra X-Ray Observatory: "Such a system could be formed as a consequence of the merger, billions of years earlier, of two galaxies that each contained a supermassive black hole. At their current close separation, the two black holes are inevitably being drawn closer together as they emit gravitational waves."

Read more about this fascinating story at: http://earthsky.org/space/andromeda-galaxy-black-holes-j004541-photobomb
Or read the full study at: https://arxiv.org/abs/1704.08694