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Latest Galaxy formation and evolution Stories

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2010-10-13 14:09:46

New observations from ESO's Very Large Telescope have, for the first time, provided direct evidence that young galaxies can grow by sucking in the cool gas around them and using it as fuel for the formation of many new stars. In the first few billion years after the Big Bang the mass of a typical galaxy increased dramatically and understanding why this happened is one of the hottest problems in modern astrophysics. The results appear in the October 14 issue of the journal Nature. The first...

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2010-10-12 10:00:00

Scientists from the Niels Bohr Institute have been studying distant galaxies, which are among the most active star-forming galaxies in the Universe. They form around 1,000 new stars a year "“ a 1,000 times more than our own galaxy, the Milky Way. The findings have been published in Monthly Notices of the Royal Astronomical Society. "The galaxies are located in the far distant Universe "“ when the universe was 3 billion years old (equivalent to only 20 percent of its current age)....

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2010-10-07 12:53:00

If you think global warming is bad, 11 billion years ago the entire universe underwent, well, universal warming. The consequence was that fierce blasts of radiation from voracious black holes stunted the growth of some small galaxies for a stretch of 500 million years. This is the conclusion of a team of astronomers who used the new capabilities of NASA's Hubble Space Telescope to probe the invisible, remote universe. Using the newly installed Cosmic Origins Spectrograph (COS) they have...

804e6cb6543a1dcb7d139a4aa5adf4ea1
2010-08-25 14:35:06

Astronomers believe they have discovered the origin of our universe's first super-massive black holes, which formed some 13 billion years ago. The discovery fills in a missing chapter of our universe's early history, and could help write the next chapter -- in which scientists better understand how gravity and dark matter formed the universe as we know it. In the journal Nature, Ohio State University astronomer Stelios Kazantzidis and colleagues describe computer simulations in which they...

70c06e4c53d0a7ae6aa7ea942b79cb56
2010-07-11 08:25:00

Galaxies like our own were built billions of years ago from a deluge of giant clouds of gas, some of which continue to rain down. Now new calculations tie the rain of giant clouds of gas to active galactic nuclei (AGN), the extremely bright centers of some galaxies. If a gas cloud with millions of times more mass than our Sun wanders too close to the center of a galaxy, it can either be consumed by the supermassive black hole that lurks there or, through shocks and collapse, give birth to new...

2539a27b566319f2a93b46527163c33b1
2010-06-30 06:25:00

Many of the Milky Way's ancient stars are remnants of other smaller galaxies torn apart by violent galactic collisions around five billion years ago, according to researchers at Durham University, who publish their results in a new paper in the journal Monthly Notices of the Royal Astronomical Society. Scientists at Durham's Institute for Computational Cosmology and their collaborators at the Max Planck Institute for Astrophysics, in Germany, and Groningen University, in Holland, ran huge...

b818a18fc0ca6c17931998c8ca7bba80
2010-06-02 07:15:00

Scientists at University College London (UCL) and the University of Cambridge have developed machine-learning codes modeled on the human brain that can be used to classify galaxies accurately and efficiently. Remarkably, the new method is so reliable that it agrees with human classifications more than 90% of the time. The research will appear in a paper in the journal Monthly Notices of the Royal Astronomical Society. There are billions of galaxies in the Universe, containing anything between...

dc02a86681c14bdfae9551c6e5c029071
2010-05-26 09:21:45

A surprising discovery that hydrogen gas clouds found in abundance in and above our Milky Way Galaxy have preferred locations has given astronomers a key clue about the origin of such clouds, which play an important part in galaxy evolution. "We've concluded that these clouds are gas that has been blown away from the Galaxy's plane by supernova explosions and the fierce winds from young stars in areas of intense star formation," said H. Alyson Ford of the University of Michigan, whose Ph.D...

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...

1ff02c5f2a78a35cc9b26a407f0b990b1
2010-05-05 09:05:00

A new wide-field image released today by ESO displays many thousands of distant galaxies, and more particularly a large group belonging to the massive galaxy cluster known as Abell 315. As crowded as it may appear, this assembly of galaxies is only the proverbial "tip of the iceberg", as Abell 315 "” like most galaxy clusters "” is dominated by dark matter. The huge mass of this cluster deflects light from background galaxies, distorting their observed shapes slightly. When...


Latest Galaxy formation and evolution Reference Libraries

45_03c916cf051c1a581c0d52b3ccdd7561
2010-09-13 16:56:08

The Coma Cluster (Abell 1656), along with the Leo Cluster, is one of two major clusters compromising the Coma Supercluster. It contains over 1000 identified galaxies. Most of the galaxies in the center of the Coma Cluster are elliptical galaxies including both dwarf and giant. However the center is dominated by NGC 4874 and NGC 4889, two giant elliptical galaxies. The brightest galaxies are visible, a few degrees north of the galactic pole, with an amateur telescope larger than 20 cm. The...

45_274ba7ddcce89663fc213d79e864e44b
2010-09-07 17:03:18

The Abell 520 galaxy cluster is an strange structure formed by a major merger. Due to its odd and chaotic nature it has been given the nick-name the Train Wreck Cluster. The Dark Matter within the cluster does not act as expected like it does in other clusters, therefore, Abell 520 creates problems for many of the prevailing theories about Dark Matter. It also disrupts many alternative theories of modified gravity. Similar to the Bullet Cluster the gas contents and galaxies within the...

6_11b0e50afd172f6a61aeda24e25504702
2004-10-19 04:45:42

Ring Galaxy -- A subclass of interacting galaxies, ring galaxies, provides a unique laboratory for studying unusually large bursts of non-nuclear star formation. The rings in these systems are often large (10s of kiloparsecs) and contain what appear to be associations of giant H{\small II} regions. As a basis for future modeling of star forming regions in observed ring galaxies we present a series of combined n-body/gas numerical experiments on ring formation and evolution. Three...

6_53083d96ff77dbf99c47ef10b6a209332
2004-10-19 04:45:41

Molecular Cloud -- Molecular clouds are interstellar nebulae that have a density and size sufficient to permit the formation of H2, molecular hydrogen. However, this molecule is difficult to detect, and the molecule most used to trace the H2 is CO (carbon monoxide). The ratio between CO luminosity and H2 mass is roughly constant, although there are reasons to doubt this assumption in observations of some other galaxies. In the Milky Way, molecular clouds account for roughly one-half...

6_46f1290db7aabf07d0480393fea260ed2
2004-10-19 04:45:41

Globular Cluster -- A globular cluster is a cluster of stars that is spherical in shape and extremely dense towards its core. Globular clusters are usually composed of hundreds of thousands of old stars, similar to the bulge of a spiral galaxy but confined to a volume of only a few cubic parsecs. Some globular clusters (like Omega Centauri in our Milky Way, and G1 in M31) are truly massive clusters, with several million times the mass of our Sun. Such globular clusters may be the...

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Word of the Day
barghest
  • A goblin in English folklore, often appearing in the shape of a large dog and believed to portend imminent death or misfortune.
  • A ghost, wraith, hobgoblin, elf, or spirit.
The origin of 'barghest' is not known, but it may be from perhaps burh-ghest, town-ghost, or German Berg-geist (mountain spirit) or Bär-geist (bear-spirit).
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