Astronomers discover dusty surprise around giant black hole

Jonathan Marker | Science Recorder | June 20, 2013

Astronomers discover dusty surprise around giant black hole

This discovery is helping scientists to understand how supermassive black holes influence their cosmic environments,

According to a June 12, 2013 press release issued by the National Aeronautics and Space Administration, a record number of black holes – 26 in all – have been observed in the Andromeda galaxy, following a 13-year review of over 150 observations transmitted from NASA’s Chandra X-ray Observatory.  According to scientists, this is the largest number of black holes ever observed in another galaxy.  Often considered the “sister galaxy” of our own Milky Way, we are on a collision course with Andromeda, and the impact is set to occur several billions of years from now.

According to Robin Barnard of Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Massachusetts, and the lead author of a new paper describing these results, “While we are excited to find so many black holes in Andromeda, we think it’s just the tip of the iceberg. Most black holes won’t have close companions and will be invisible to us.”  The paper is titled “Chandra identification of 26 new black hole candidates in the central region of M31.”

In addition to the Chandra findings for the Andromeda galaxy, scientists working with the European Southern Observatory’s (ESO) Very Large Telescope Interferometer have gathered the most detailed observations ever of the dust around the huge black hole at the center of a nearby galaxy called NGC 3783, according to a June 20, 2013 ESO press release.

In a surprising find, scientists observed that dust is currently being pushed away from the black hole as a “cool wind.”  This discovery is helping scientists to understand how supermassive black holes influence their cosmic environments and how these mysterious beasts evolve.  The findings have been published in The Astrophysical Journal under the title, “Dust In The Polar Region As A Major Contributor To The Infrared Emission Of Active Galactic Nuclei.”

According to lead author Sebastian Hönig of the University of California Santa Barbara, “This is the first time we’ve been able to combine detailed mid-infrared observations of the cool, room-temperature dust around an AGN with similarly detailed observations of the very hot dust. This also represents the largest set of infrared interferometry for an AGN published yet.”

And, according to Gerd Weigelt, another team member from Max Planck Institute for Astrophysics in Bonn, Germany, “By combining the world-class sensitivity of the large mirrors of the VLT with interferometry we are able to collect enough light to observe faint objects. This lets us study a region as small as the distance from our Sun to its closest [neighboring] star, in a galaxy tens of millions of light-years away. No other optical or infrared system in the world is currently capable of this.”


Print article

Comments should take into account that readers may hold different opinions. With that in mind, please make sure comments are respectful, insightful, and remain focused on the article topic. In addition, readers can send us tips, press releases, or ideas for stories: