Astronomers have found that the most luminous known galaxy in the universe appears to be tearing itself apart. Named W2246-0526, it is found 12.4 billion light-years from Earth – and has a huge black hole that is churning its material.
Scientists studied the galaxy using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, although it was first discovered by NASA’s Wide-field Infrared Survey Explorer (WISE). They found that the galaxy, which formed about a billion years after the Big Bang 13.7 billion years ago and shines as bright as 300 trillion Suns, is expelling gas due to the intense amount of energy from the black hole.
This is the first time such a phenomenon has ever been seen in a galaxy like this. The findings are to be published in The Astrophysical Journal Letters. A pre-print is available on Arxiv.
"This galaxy is tearing itself apart," Roberto Assef, an astronomer with the Universidad Diego Portales in Chile and leader of the observing team at ALMA, said in a statement. "The momentum and energy of the particles of light deposited in the gas are so great that they are pushing the gas out in all directions."
W2246-0526 is a rare galaxy known as a Hot, Dust-Obscured Galaxy, or a Hot DOG (seriously). In galaxies like this, an intensely bright and hot region of material around the central supermassive black hole, known as an accretion disk, rages.
But unlike other Hot DOGs, where turbulent gas from this process is found localized in one direction, W2246-0526 has turbulent gas across the whole galaxy, spanning thousands of light-years.
The gas is moving through the galaxy at about 2 million kilometers (1.2 million miles) an hour. It’s thought that the intense luminosity of the galaxy could be the cause of this unusual behavior. In fact, the region around its black hole is more than 100 times more luminous than the rest of the galaxy, exerting huge pressure on the gas within. If these turbulent conditions continue, all of the galaxy’s interstellar gas could be “boiled away.”
The big unknown at the moment is whether this gas is actually being pushed out of the galaxy, or whether it is simply churning around. "A likely finale would be that the galaxy will blow out all of the gas and dust that is surrounding it, and we would see the accretion disk without its dust cover – what we call a quasar," Assef added.