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Latest Active galactic nucleus Stories

d10aab7e1cb240052c84ba9a13f65584
2011-01-05 07:50:00

What happens when galaxies crash together? For years, these cosmic collisions have been blamed for triggering violent outbursts at the hearts of galaxies. Now, a remarkable piece of detective work has given a verdict: galactic mergers do not usually whet the appetite of the black holes that power these active galactic nuclei, meaning other, less dramatic phenomena are responsible. Most galaxies, including our own, have a huge but well-behaved black hole at their heart, while some have messy...

9c3dbd5f97b039fc95955f27cbbc6dd51
2010-12-20 14:57:21

A new study from NASA's Chandra X-ray Observatory tells scientists how often the biggest black holes have been active over the last few billion years. The object could help scientists better understand how massive stars explode, which ones leave behind black holes or neutron stars, and how many black holes are in our galaxy and others. This discovery clarifies how supermassive black holes grow and could have implications for how the giant black hole at the center of the Milky Way will behave...

3e011e44ef382f2b451e75e436e722321
2010-11-25 06:36:54

New findings disagree with current models Some of the universe's most massive galaxies may have formed billions of years earlier than current scientific models predict, according to surprising new research led by Tufts University. The findings appear in the Astrophysical Journal published online Nov. 24 in advance of print publication on Dec. 10, 2010. "We have found a relatively large number of very massive, highly luminous galaxies that existed almost 12 billion years ago when the universe...

59e94558e9c3b803ad152dd148a5a82d
2010-07-01 06:20:00

Evidence for a recoiling black hole has been found using data from the Chandra X-ray Observatory, XMM-Newton, the Hubble Space Telescope (HST), and several ground-based telescopes. This black hole kickback was caused either by a slingshot effect produced in a triple black hole system, or from the effects of gravitational waves produced after two supermassive black holes merged a few million years earlier. The discovery of this object, located in this composite image, comes from a large,...

c2b6a5ac876bca939f643a62437d01141
2010-06-24 13:05:00

Using two of the world's largest telescopes, an international team of astronomers have found evidence of a collision between galaxies driving intense activity in a highly luminous quasar. The scientists, led by Montserrat Villar Martin of the Instituto de Astrofisica de Andalucía-CSIC in Spain, used the Very Large Telescope (VLT) in Chile and the Gran Telescopio Canarias (GTC) on La Palma in the Canary Islands, to study activity from the quasar SDSS J0123+00. They publish...

8da1072ff406aa94af2de983e69617321
2010-05-26 12:50:00

Data from an ongoing survey by NASA's Swift satellite have helped astronomers solve a decades-long mystery about why a small percentage of black holes emit vast amounts of energy. Only about one percent of supermassive black holes exhibit this behavior. The new findings confirm that black holes "light up" when galaxies collide, and the data may offer insight into the future behavior of the black hole in our own Milky Way galaxy. The study will appear in the June 20 issue of The Astrophysical...

2010-05-26 11:50:00

WASHINGTON, May 26 /PRNewswire-USNewswire/ -- Data from an ongoing survey by NASA's Swift satellite have helped astronomers solve a decades-long mystery about why a small percentage of black holes emit vast amounts of energy. (Logo: http://www.newscom.com/cgi-bin/prnh/20081007/38461LOGO) Only about one percent of supermassive black holes exhibit this behavior. The new findings confirm that black holes "light up" when galaxies collide, and the data may offer insight into the future...

c05bf85543904881ee1980d79840080f1
2010-05-25 14:01:50

Previous galaxy merger is likely cause A team of astronomy researchers at Florida Institute of Technology and Rochester Institute of Technology in the United States and University of Sussex in the United Kingdom, find that the supermassive black hole (SMBH) at the center of the most massive local galaxy (M87) is not where it was expected. Their research, conducted using the Hubble Space Telescope (HST), concludes that the SMBH in M87 is displaced from the galaxy center. The most likely cause...

e403e3516a8579c6377682457e91f86e1
2010-05-11 13:37:18

Using observations with NASA's Chandra X-ray Observatory and ESA's XMM-Newton, astronomers have announced a robust detection of a vast reservoir of intergalactic gas about 400 million light years from Earth. This discovery is the strongest evidence yet that the "missing matter" in the nearby Universe is located in an enormous web of hot, diffuse gas. This missing matter "” which is different from dark matter -- is composed of baryons, the particles, such as protons and electrons, that...

9699d9480972f837f3db19a931a0eed41
2010-05-11 10:00:00

Supermassive black holes with the mass of many millions of stars have been detected at the center of many large galaxies. A super-massive black hole acts like a lurking "monster" at the center of the galaxy which swallows the surrounding material through the intensity of its gravitational pull. X-ray observations indicate that a large amount of energy is produced by the in-fall of matter into a black hole, and ejected in powerful jets. Astronomers from the Max Planck Institute for...


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
Cthulhu
  • A gigantic fictional humanoid alien god being described with a head resembling an octopus and dragon wings and claws, around whom an insane cult developed.
  • Pertaining to the mythos of Cthulhu and additional otherworldly beings created by H. P. Lovecraft or inspired by his writings and imitators.
This word was invented in 1926 by H.P. Lovecraft for his short story, 'The Call of Cthulhu.' 'Cthulhu' may be based on the word 'chthonic,' which in Greek mythology refers to the underworld.
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