Featured Research

from universities, journals, and other organizations

Clouds seen circling supermassive black hole

Date:
February 19, 2014
Source:
Royal Astronomical Society (RAS)
Summary:
Astronomers see huge clouds of gas orbiting supermassive black holes at the centres of galaxies. Once thought to be a relatively uniform, fog-like ring, the accreting matter instead forms clumps dense enough to intermittently dim the intense radiation blazing forth as these enormous objects condense and consume matter.

Artist's concept of a supermassive black hole at the centre of a galaxy.
Credit: NASA / JPL / Caltech

Astronomers see huge clouds of gas orbiting supermassive black holes at the centres of galaxies. Once thought to be a relatively uniform, fog-like ring, the accreting matter instead forms clumps dense enough to intermittently dim the intense radiation blazing forth as these enormous objects condense and consume matter.

The international team reports their sightings in a paper to be published in the Monthly Notices of the Royal Astronomical Society.

Evidence for the clouds comes from records collected over 16 years by NASA's Rossi X-ray Timing Explorer, a satellite in low-earth orbit equipped with instruments that measured variations in X-ray sources. Those sources include active galactic nuclei, brilliantly luminous objects powered by supermassive black holes as they gather and condense huge quantities of dust and gas.

By sifting through records for 55 active galactic nuclei Alex Markowitz, an astrophysicist at the University of California, San Diego and the Karl Remeis Observatory in Bamberg, Germany and colleagues found a dozen instances when the X-ray signal dimmed for periods of time ranging from hours to years, presumably when a cloud of dense gas passed between the source and satellite.

Mirko Krumpe of the European Southern Observatory in Garching, Germany and Robert Nikutta, of Andrιs Bello University in Santiago, Chile co-authored the report, which confirms what recent models of these systems have predicted.

The clouds they observed orbit a few light-weeks to a few light-years from the centre of the active galactic nuclei. One, in a spiral galaxy in the direction of the constellation Centaurus designated NGC 3783, appeared to be in the midst of being torn apart by tidal forces.

Support for this research came from NASA's Astrophysics Data Analysis Program (NNX11AD07G) and the European Community's Seventh Framework Program (229517). Nikutta acknowledges support from ALMA-CONICYT (31110001). Video produced by the Scientific Visualization Studio, Goddard Spaceflight Centre, NASA, based in part on visualisations created by Wolfgang Steffen, Institute of Astronomy, National Autonomous University of Mexico.


Story Source:

The above story is based on materials provided by Royal Astronomical Society (RAS). Note: Materials may be edited for content and length.


Journal Reference:

  1. A. G. Markowitz, M. Krumpe, R. Nikutta. First X-ray-based statistical tests for clumpy-torus models: eclipse events from 230 years of monitoring of Seyfert AGN. Monthly Notices of the Royal Astronomical Society, 2014; DOI: 10.1093/mnras/stt2492

Cite This Page:

Royal Astronomical Society (RAS). "Clouds seen circling supermassive black hole." ScienceDaily. ScienceDaily, 19 February 2014. <www.sciencedaily.com/releases/2014/02/140219124621.htm>.
Royal Astronomical Society (RAS). (2014, February 19). Clouds seen circling supermassive black hole. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2014/02/140219124621.htm
Royal Astronomical Society (RAS). "Clouds seen circling supermassive black hole." ScienceDaily. www.sciencedaily.com/releases/2014/02/140219124621.htm (accessed September 1, 2014).

Share This




More Space & Time News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Space Shuttle Discovery's Legacy, 30 Years Later

Space Shuttle Discovery's Legacy, 30 Years Later

Newsy (Aug. 30, 2014) — The space shuttle Discovery launched for the very first time 30 years ago. Here's a look back at its legacy. Video provided by Newsy
Powered by NewsLook.com
Experiment Tests Whether Universe Is Actually A Hologram

Experiment Tests Whether Universe Is Actually A Hologram

Newsy (Aug. 27, 2014) — Researchers at Fermilab are using a device called "The Holometer" to test whether our universe is actually a 2-D hologram that just seems 3-D. Video provided by Newsy
Powered by NewsLook.com
SpaceX’s Falcon 9 Rocket Explodes After Liftoff

SpaceX’s Falcon 9 Rocket Explodes After Liftoff

Newsy (Aug. 23, 2014) — The private spaceflight company says it is preparing a thorough investigation into Friday's mishap. Video provided by Newsy
Powered by NewsLook.com
Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Newsy (Aug. 21, 2014) — Russian cosmonauts say they've found evidence of sea plankton on the International Space Station's windows. NASA is a little more skeptical. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins