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Latest Active galactic nucleus Stories

quasar UM287
2014-01-20 04:49:41

redOrbit Staff & Wire Reports - Your Universe Online A distant quasar discovered by astronomers working at Hawaii’s WM Keck Observatory has for the first time revealed part of the filament networks believed to connect galaxies in a cosmic web, according to research published Sunday in the journal Nature. Using the observatory’s 10-meter Keck I Telescope, a team of researchers including first author Sebastiano Cantalupo, a postdoctoral fellow at the University of California,...

First Gamma Ray Study Gravitational Lens
2014-01-06 15:27:47

[ Watch the Video: Fermi Provides New Details About Gravitational Lenses ] Brett Smith for redOrbit.com - Your Universe Online A gravitational lens is created when a galaxy or other massive object bends and amplifies light heading toward an observer from a more distant source and a new paper from an international team of researchers has reported the first-ever gamma ray study of the cosmic phenomenon. The paper, which will be published in an upcoming edition of Astrophysical Journal...

Virtual Observatory Study Explains How Black Holes Get So Massive
2013-10-17 12:57:02

Lee Rannals for redOrbit.com - Your Universe Online Astronomers using a "Virtual Observatory" set out to study "fat" black holes that grow up to more than one million solar masses. Some massive black holes are observed as active galactic nuclei (AGN), which attract surrounding gas and release huge amounts of energy. The team collected the data on more than 10,000 AGN whose black hole mass had already been measured by spectroscopic observation. Scientists have wondered exactly how a...

Black Hole Blows Powerful Streams
2013-09-06 08:51:29

April Flowers for redOrbit.com - Your Universe Online A worldwide network of radio telescopes has allowed astronomers to find strong evidence that a powerful jet of material, propelled to nearly light speed by the central black hole of a galaxy, is blowing massive amounts of gas out of the host galaxy. The scientists say the process is limiting the growth of the black hole and the rate of star formation in the galaxy. That makes the process a key to understanding how galaxies develop....

Black Hole Observed Pushing Matter Away, Rather Than Consuming It
2013-06-20 06:27:46

Lawrence LeBlond for redOrbit.com - Your Universe Online Observations of a nearby active galaxy using the Very Large Telescope Interferometer (VLTI) at ESO´s Paranal Observatory in Chile have shown astronomers something they hadn´t expected to see. Astronomers have found over the past twenty years that nearly all galaxies have a black hole at their center, some of which grow by drawing in matter from their surroundings. This growth process creates some of the most energetic objects...

Most Distant Source Of High-Energy Gamma Rays Comes From Distant Blazar
2013-04-19 04:57:41

April Flowers for redOrbit.com - Your Universe Online Of all the active galactic nuclei, blazars are the brightest and emit very high-energy gamma rays. A team led by physicists from the University of California, Santa Cruz (UCSC), has made new observations of the blazar known as PKS 1424+240 that reveal it is the most distant known source of very high-energy gamma rays. The emission spectrum of PKS 1424+240 now appears highly unusual in the light of new data. Data from the Hubble Space...

Sideline Quasars May Have Hampered Galaxy Formation
2013-03-22 04:19:47

redOrbit Staff & Wire Reports - Your Universe Online Astronomers from the University of Colorado Boulder (CU-Boulder) believe that so-called sideline quasars located on the outer fringes of a larger, brighter active galactic nucleus might have joined forces with it to prevent the formation of small galaxies billions of years ago. Michael Shull, a professor of astrophysical and planetary sciences at the university´s Center for Astrophysics and Space Astronomy, and research...

NASA X-Ray Observatories Reveal Black Hole Spin
2013-02-27 17:22:50

John P. Millis, PhD for redOrbit.com — Your Universe Online One of the challenges of studying black holes — incredibly dense stellar remnants arising from massive supernova explosions — is that it is extremely difficult to measure the spin of such objects. And it is this motion that is of particular interest, since Einstein´s theory of General Relativity predicts that the gravitational waves produced from their rotation can distort the very fabric of space-time...


Latest Active galactic nucleus Reference Libraries

6_c7a74d948ad4cfdc1dd54ceada2509fb2
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....

6_0ba47eab12382e6a4e2cc12b1c7ddf782
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...

6_3e166ea744352dc86330d77d6feb4abd2
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...

3_54318e1880d81bf6c92376b6217cbdef2
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
omphalos
  • The navel or umbilicus.
  • In Greek archaeology: A central boss, as on a shield, a bowl, etc.
  • A sacred stone in the temple of Apollo at Delphi, believed by the Greeks to mark the 'navel' or exact center-point of the earth.
'Omphalos' comes from the ancient Greek.
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