Astronomers spot ‘cosmic rainstorm’ feeding supermassive black hole
Using the Atacama Large Millimeter/submillimeter Array (ALMA) radio telescopes in Chile, scientists have observed a novel cosmic weather phenomenon: imposing intergalactic gas clouds raining in on a supermassive black hole in the middle of an elliptical galaxy located one billion light-years from Earth.
According to a report set to be published in the journal Nature, the new findings are the first time astronomers have seen cold dense clouds can form out of hot intergalactic gas and dive into the center of a galaxy, feeding its central supermassive black hole. They also reshape astronomers’ thoughts about how supermassive black holes consume material through a process referred to as accretion.
Past research had shown, in the largest galaxies, supermassive black holes are provided with on a steady and slow regimen of hot gas from the galaxy’s halo. The new observations indicate that, when the intergalactic weather is just right, black holes can also feed on a downpour of massive, very clouds of gas.
An artist’s impression of the cosmic rain. Credit: NRAO/AUI/NSF; Dana Berry/SkyWorks; ALMA (ESO/NAOJ/NRAO)
“This so-called cold, chaotic accretion has been a major theoretical prediction in recent years, but this is one of the first unambiguous pieces of observational evidence for a chaotic, cold ‘rain’ feeding a supermassive black hole,” Grant Tremblay, an astronomer with Yale University, told redOrbit in a statement. “It’s exciting to think we might actually be observing this galaxy-spanning ‘rainstorm’ feeding a black hole whose mass is about 300 million times that of our Sun.”
Using ALMA, the study team looked into a highly luminous cluster of around 50 galaxies, collectively referred to as Abell 2597. At its center is a singular immense elliptical galaxy, dubbed the Abell 2597 Brightest Cluster Galaxy. In the space between these galaxies is a dissipate atmosphere of very hot, ionized plasma, which was prior identified with NASA’s Chandra X-ray Observatory.
“This very, very hot gas can quickly cool, condense, and precipitate in much the same way that warm, humid air in Earth’s atmosphere can spawn rain clouds and precipitation,” Tremblay said. “The newly condensed clouds then rain in on the galaxy, fueling star formation and feeding its supermassive black hole.”
The researchers found the gas clouds are speeding toward the supermassive black hole at a rate of about 670,000 miles per hour. Each cloud holds enough material for a million Suns and is tens of light-years across.
While ALMA was just capable of identifying three of these clouds, the study team said that there might be thousands like them nearby, priming the black hole for a extended downpour that could fuel its activity well into the future.
The study authors said they now intend to use ALMA in a larger search for these “rainstorms” in other galaxies to ascertain if such cosmic weather is as typical as existing theory indicates it to be.
—–
Image credit: ALMA/ESO
The post Astronomers spot ‘cosmic rainstorm’ feeding supermassive black hole appeared first on Redorbit.
redOrbit.com
offers Science, Space, Technology, Health news, videos, images and reference information. For the latest science news, space news, technology news, health news visit redOrbit.com frequently. Learn something new every day.”
Source: http://www.redorbit.com/news/space/1113414459/cosmic-rainstorm-060816/
