NASA | MSFC | SAO | Chandra X-ray Observatory | 2017 Nov 30
[img3="X-ray: NASA/CXC/Univ. of Washington/T. Dorn-Wallenstein et al.;An intriguing source has been discovered in the nearby Andromeda galaxy using data from NASA's Chandra X-ray Observatory and ground-based optical telescopes. Previously thought to be part of the Milky Way's neighbor galaxy, the new research shows this source is actually a very distant object 2.6 billion light years away that is acting as a cosmic bomb, as reported in our press release.
Optical: NASA/ESA/J. Dalcanton, et al. & R. Gendler "]http://chandra.si.edu/photo/2017/m31/m31.jpg[/img3][hr][/hr]
This graphic shows the Chandra data (blue in inset) of the source known as LGGS J004527.30+413254.3 (J0045+41 for short) in the context of optical images of Andromeda from the Hubble Space Telescope. In the inset image, north is up and in the large image north is to the lower right. Andromeda, also known as M31, is a spiral galaxy located about 2.5 million light years from Earth.
Even more intriguing than the large distance of J0045+41 is that it likely contains a pair of giant black holes in close orbit around each other. The estimated total mass for these two supermassive black holes is about two hundred million times that of our Sun. ...
A Mote in Andromeda's Disk: A Misidentified Periodic AGN Behind M31 - Trevor Dorn-Wallenstein, Emily M. Levesque, John J. Ruan