Latest Active galactic nucleus Stories

2011-06-11 07:05:00

A study using NASA's Swift satellite and the Chandra X-ray Observatory has found a second supersized black hole at the heart of an unusual nearby galaxy already known to be sporting one. The galaxy, which is known as Markarian 739 or NGC 3758, lies 425 million light-years away toward the constellation Leo. Only about 11,000 light-years separate the two cores, each of which contains a black hole gorging on infalling gas. The study will appear in a forthcoming issue of The Astrophysical Journal...

2011-06-06 11:25:00

Active galactic nuclei By studying the X-rays emitted when superheated gases plunge into distant and massive black holes, astrophysicists at the Georgia Institute of Technology have provided an important test of a long-standing theory that describes the extreme physics occurring when matter spirals into these massive objects. Matter falling into black holes emits tremendous amounts of energy which can escape as visible light, ultraviolet light and X-rays. This energy can also drive outflows...

2011-05-20 14:29:00

WASHINGTON, May 20, 2011 /PRNewswire-USNewswire/ -- An international team, including NASA-funded researchers, using radio telescopes located throughout the Southern Hemisphere, has produced the most detailed image of particle jets erupting from a supermassive black hole in a nearby galaxy. (Logo: http://photos.prnewswire.com/prnh/20081007/38461LOGO) "These jets arise as infalling matter approaches the black hole, but we don't yet know the details of how they form and maintain...

2011-05-20 14:30:00

An international team, including NASA-funded researchers, using radio telescopes located throughout the Southern Hemisphere has produced the most detailed image of particle jets erupting from a supermassive black hole in a nearby galaxy. "These jets arise as infalling matter approaches the black hole, but we don't yet know the details of how they form and maintain themselves," said Cornelia Mueller, the study's lead author and a doctoral student at the University of Erlangen-Nuremberg in...

2011-05-03 06:30:00

Berkeley Lab-led BOSS proves it can do the job with quasars The biggest 3-D map of the distant universe ever made, using light from 14,000 quasars "“ supermassive black holes at the centers of galaxies billions of light years away "“ has been constructed by scientists with the third Sloan Digital Sky Survey (SDSS-III). The map is the first major result from the Baryon Oscillation Spectroscopic Survey (BOSS), SDSS-III's largest survey, whose principal investigator is David Schlegel...

2011-03-02 13:39:54

Using a perfectly orchestrated world-wide network of radio telescopes, astronomers have produced a high-resolution map of an Active Galactic Nucleus (AGN) belonging to an unknown class of gamma-ray sources. The unusual source and the groundbreaking technique used to produce the image are detailed in a letter published today in Astronomy & Astrophysics. The paper, "Global e-VLBI observations of the gamma-ray narrow line Seyfert 1 PMN J0948+0022" (abstract, full html, PDF), presents very...

2011-02-25 11:55:00

When two galaxies merge to form a giant, the central supermassive black hole in the new galaxy develops an insatiable appetite. However, this ferocious appetite is unsustainable. For the first time, observations with the Gemini Observatory clearly reveal an extreme, large-scale galactic outflow that brings the cosmic dinner to a halt. The outflow is effectively blowing the galaxy apart in a negative feedback loop, depriving the galaxy's monstrous black hole of the gas and dust it needs to...

2011-01-20 12:53:49

Seen in X-rays, the entire sky is aglow. Even far away from bright sources, X-rays originating from beyond our galaxy provide a steady glow in every direction. Astronomers have long suspected that the chief contributors to this cosmic X-ray background were dust-swaddled black holes at the centers of active galaxies. The trouble was, too few of them were detected to do the job. An international team of scientists using data from NASA's Swift satellite confirms the existence of a largely unseen...

2011-01-12 13:44:18

Astronomers at the California Institute of Technology (Caltech), University of Illinois at Urbana-Champaign (UIUC), and University of Hawaii (UH) have discovered 16 close-knit pairs of supermassive black holes in merging galaxies. The discovery, based on observations done at the W. M. Keck Observatory on Hawaii's Mauna Kea, is being presented in Seattle on January 12 at the meeting of the American Astronomical Society, and has been submitted for publication in the Astrophysical Journal. These...

2011-01-10 08:29:08

Discovery gives important clues about a previously-unobserved, very early phase of galaxy evolution The surprising discovery of a supermassive black hole in a small nearby galaxy has given astronomers a tantalizing look at how black holes and galaxies may have grown in the early history of the Universe. Finding a black hole a million times more massive than the Sun in a star-forming dwarf galaxy is a strong indication that supermassive black holes formed before the buildup of galaxies, the...

Latest Active galactic nucleus Reference Libraries

2004-10-19 04:45:42

Seyfert Galaxy -- Seyfert galaxies are spiral or irregular galaxies containing an extremely bright nucleus, most likely caused by a supermassive black hole, that can sometimes outshine the surrounding galaxy. The light from the central nucleus varies in less than a year, which implies that the emitting region must be less than one light year across. They are named for the astronomer Carl Seyfert, who studied them extensively in the 1940s. They are a subclass of active galactic nuclei....

2004-10-19 04:45:42

Quasar -- A quasar (from quasi-stellar radio source) is an astronomical object that looks like a star in optical telescopes (i.e. it is a point source), but has a very high redshift. The general consensus is that this high redshift is cosmological, the result of Hubble's law and that their redshift indicates that they are typically very distant from Earth; we observe them as they were several billions of years ago. Since we can see them despite their distance, they must emit more...

2004-10-19 04:45:41

Active Galaxy -- An active galaxy is a galaxy where a significant fraction of the energy output is not emitted from normal stellar populations or interstellar gas. This energy, depending on the active galaxy type, can be emitted across most of the electromagnetic spectrum, as infrared, radio waves, UV, X-ray and gamma rays. Frequently, the abbreviation AGN (Active Galactic Nuclei) is used, since most of the active galaxies emit most of their radiation from a narrow region in their...

2004-10-19 04:45:40

Circinus Galaxy -- Resembling a swirling witch's cauldron of glowing vapors, the black hole-powered core of a nearby active galaxy appears in this colorful NASA Hubble Space Telescope image. The galaxy lies 13 million light-years away in the southern constellation Circinus. This galaxy is designated a type 2 Seyfert, a class of mostly spiral galaxies that have compact centers and are believed to contain massive black holes. Seyfert galaxies are themselves part of a larger class of objects...

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Word of the Day
  • Licking.
  • Hence Running along or over a surface, as if in the act of licking; flowing over or along; lapping or bathing; softly bright; gleaming.
This word comes the Latin 'lambere,' to lick.