Brightest galaxy discovered

Black hole cooks cosmic dust to produce brilliant infrared light

WEAR SHADES Light pours out of the brightest known galaxy (illustrated), which is about 350 trillion times as bright as the sun.

JPL-Caltech/NASA

By Christopher Crockett

May 26, 2015 at 11:49 am

The most luminous known galaxy blasts out as much light as roughly 350 trillion suns, researchers report in the June 1 Astrophysical Journal.

A supermassive black hole lurking in the galaxy’s core probably powers this cosmic beacon, Chao-Wei Tsai, an astronomer at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and colleagues report. They found the galaxy while scouring data from the WISE satellite, which spent about a year surveying the sky for anything glowing in infrared. The infrared light from this galaxy, dubbed W2246-0526, comes from dust heated by a blazing-hot disk of gas churning around the black hole.

The high temperatures and blankets of dust have earned this galaxy and others like it the moniker Hot DOGs, for hot dust-obscured galaxies. The light from this Hot DOG, which lurks in the constellation Aquarius, took 12.4 billion years to reach Earth.