Most luminous galaxy is ripping itself apart

In a far-off galaxy, 12.4 billion light-years from Earth, a ravenous black hole is devouring galactic grub. Its feeding frenzy produces so much energy, it stirs up gas across its entire galaxy.

This galaxy, called W2246-0526, is the most luminous galaxy known, according to research published in 2015 – and involving our University - based on data from NASA’s Wide-field Infrared Survey Explorer (WISE). That means that it has the highest power output of any galaxy in the universe, and would appear to shine the brightest if all galaxies were at the same distance from us.

Professor Andrew Blain (pictured), from the Department of Physics and Astronomy, a WISE team member, was co-author of the report into the discovery of the galaxy last year.  Now he and colleagues have reported new findings about the galaxy in The Astrophysical Journal Letters, which have revealed that this galaxy is also expelling tremendously turbulent gas - a phenomenon never seen before in an object of this kind.

Professor Blain said: “The study provides a look at this object in unprecedentedly fine detail, and shows the motion of the gas within. I’m involved in getting and  interpreting this data. It really does seem to be a case of the galaxy “blowing itself up in all directions", unlike the more usual situation where material flows out in two back-to-back directions. It’s even more dramatic than we’d expected. It reminds me a little of Wile E. Coyote having some horrible self-inflicted accident.”

Astronomers found large amounts of ionised carbon in a very turbulent state throughout the entire galaxy. The galaxy formed a little over 1 billion years after the big bang.

This galaxy is an example of a rare class of objects called Hot, Dust-Obscured Galaxies or Hot DOGs, which are powerful galaxies with supermassive black holes in their centers. Only 1 out of every 3,000 galaxies that WISE has observed is in this category.

The WISE mission was essential to finding this galaxy because the galaxy is covered in dust, obscuring its light from visible-wavelength telescopes. The dust shifts the light from the galaxy into the infrared range, to which WISE is attuned.