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Latest Active galactic nucleus Stories

51e9562ee037aa87fd6aa7f00e8660c81
2009-05-14 17:20:00

Activity from a supermassive black hole is responsible for the intriguing appearance of this galaxy, 3C305, located about 600 million light years away from Earth. The structures in red and light blue are X-ray and optical images from the Chandra X-ray Observatory and Hubble Space Telescope respectively. The optical data is from oxygen emission only, and therefore the full extent of the galaxy is not seen. Radio data are shown in darker blue and are from the National Science Foundation's Very...

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2009-04-23 09:32:24

An international team of astronomers has used the world's biggest radio telescope to look deep into the brightest galaxies that NASA's Fermi Gamma-ray Space Telescope can see. The study solidifies the link between an active galaxy's gamma-ray emissions and its powerful radio-emitting jets. "Now we know for sure that the fastest, most compact, and brightest jets we see with radio telescopes are the ones that are able to kick light up to the highest energies," said Yuri Kovalev, a team member...

7c58aaf8139064599584992fabd499981
2009-03-19 09:50:00

An international team of astrophysicists using telescopes on the ground and in space have uncovered surprising changes in radiation emitted by an active galaxy. The picture that emerges from these first-ever simultaneous observations with optical, X-ray and new-generation gamma-ray telescopes is much more complex than scientists expected and challenges current theories of how the radiation is generated. The galaxy in question is PKS 2155-304, a type of object known as a "blazar." Like many...

cbad4b79dd7c15a3ab0aa10f5bbd77a61
2009-03-05 06:50:00

Two enormous black holes appear to be orbiting one another at the center of a faraway galaxy, formed by the collision of two separate galaxies, astronomers from the National Optical Astronomy Observatory (NOAO) in Tucson reported Wednesday. The two supermassive black holes are locked in orbit about 5 billion light years away from Earth, the scientists said.  One light year is the distance light travels in a year, approximately 6 trillion miles. Data from Apache Point Observatory in New...

872fa0b5c8b3109ab90d8991dd9e633a1
2009-01-28 07:50:00

Astronomers have a new insight into the active galaxy Centaurus A (NGC 5128), as the jets and lobes emanating from the central black hole have been imaged at submillimeter wavelengths for the first time. The new data, from the Atacama Pathfinder Experiment (APEX) telescope in Chile, which is operated by ESO, have been combined with visible and X-ray wavelengths to produce this striking new image. Centaurus A is our nearest giant galaxy, at a distance of about 13 million light-years in the...

5ccfb11219c86886e258ca6821c1a6de1
2009-01-22 09:51:30

A team of Yale University astronomers has discovered that galaxies stop forming stars long before their central supermassive black holes reach their most powerful stage, meaning the black holes can't be responsible for shutting down star formation. Until recently, astronomers believed that active galactic nuclei (AGN)"”the supermassive, extremely energetic black holes at the centers of many young galaxies"”were responsible for shutting down star formation in their host galaxies...

2009-01-06 14:21:00

GREENBELT, Md., Jan. 6 /PRNewswire-USNewswire/ -- An ongoing X-ray survey undertaken by NASA's Swift spacecraft is revealing differences between nearby active galaxies and those located about halfway across the universe. Understanding these differences will help clarify the relationship between a galaxy and its central black hole. (Logo: http://www.newscom.com/cgi-bin/prnh/20081007/38461LOGO) "There's a lot we don't know about the workings of supermassive black holes," says Richard...

ff7a4fb10a612a33d0f272e2f9a26e5d1
2008-12-16 15:32:58

Seeing the shape of material around black holes for first time Black holes can now be thought of as donut holes. The shape of material around black holes has been seen for the first time: an analysis of over 200 active galactic nuclei"”cores of galaxies powered by disks of hot material feeding a super-massive black hole"”shows that all have a consistent, ordered physical structure that seems to be independent of the black hole's size. "This should be a very messy and complicated...

12bff1736872369004d532cce042509e1
2008-09-17 14:20:00

XMM-Newton has uncovered a well-tuned periodic signal from a super-massive black hole lodged at the centre of a galaxy, ending a long quest for such an object. The discovery provides scientists with a clearer picture on black hole accretion processes and an excellent tool to study active galactic nuclei (AGNs). These periodic signals originating from the black hole are emitted in X-rays, which are blocked out by the Earth's atmosphere. So the team used data from ESA's orbiting X-ray...

3cc2030f54079dabcad067e9b656f86e1
2008-07-24 09:27:26

For the first time, a team of international researchers has found a way to view the accretion disks surrounding black holes and verify that their true electromagnetic spectra match what astronomers have long predicted they would be. Their work will be published in the July 24 issue of the science journal Nature. A black hole and its bright accretion disk have been thought to form a quasar, the powerful light source at the center of some distant galaxies. Using a polarizing filter, the...


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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glogg
  • Scandinavian punch made of claret and aquavit with spices and raisins and orange peel and sugar.
This word comes from the Swedish 'glogg,' which is an alteration of 'glodgat,' mulled (wine).
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