Latest Galaxy formation and evolution Stories

2011-08-22 16:37:42

A CSIRO study has shown why the lights are going out in the Universe. The Universe forms fewer stars than it used to, and a CSIRO study has now shown why - the galaxies are running out of gas. Dr. Robert Braun (CSIRO Astronomy and Space Science) and his colleagues used CSIRO´s Mopra radio telescope near Coonabarabran, NSW, to study far-off galaxies and compare them with nearby ones. Light (and radio waves) from the distant galaxies has taken time to travel to us, so we see the...

2011-08-18 07:25:00

Observations from ESO's Very Large Telescope have shed light on the power source of a rare vast cloud of glowing gas in the early Universe. The observations show for the first time that this giant "Lyman-alpha blob" "” one of the largest single objects known "” must be powered by galaxies embedded within it. The results appear in the 18 August issue of the journal Nature. A team of astronomers has used ESO's Very Large Telescope (VLT) to study an unusual object called a...

2011-06-21 13:29:27

Astronomers have probed into the distant universe and discovered that galaxies display one of two distinct behaviors: they are either awake or asleep, actively forming stars or are not forming any new stars at all. Scientists have known for several years that galaxies in the nearby universe seem to fall into one of these two states. But a new survey of the distant universe shows that even very young galaxies as far away as 12 billion light years are either awake or asleep as well, meaning...

2011-06-15 12:00:00

WASHINGTON, June 15, 2011 /PRNewswire-USNewswire/ -- Using the deepest X-ray image ever taken, astronomers found the first direct evidence that massive black holes were common in the early universe. This discovery from NASA's Chandra X-ray Observatory shows that very young black holes grew more aggressively than previously thought, in tandem with the growth of their host galaxies. (Logo: http://photos.prnewswire.com/prnh/20081007/38461LOGO) By pointing Chandra at a patch of sky for more...

2011-06-15 09:30:00

A unique example of some of the lowest surface brightness galaxies in the universe have been found by an international team of astronomers lead by the Niels Bohr Institute. The galaxy has lower amounts of heavier elements than other known galaxies of this type. The discovery means that small low surface brightness galaxies may have more in common with the first galaxies formed shortly after the Big Bang than previously thought. The results have been published in Monthly Notices of the Royal...

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...

2011-06-01 10:00:00

Astronomers have discovered another galaxy about 30 million light years away that looks like a giant Milky Way "clone". The galaxy would be identical to the Milky Way if its diameter was not twice that of the Milky Way. "This view could almost be a picture postcard of our own Milky Way, taken and sent by an extragalactic friend, as this galaxy closely resembles our own," the European Southern Observatory (ESO) said in a statement. The galaxy lies about 30 million light years away, in the...

2011-06-01 08:40:24

University of Michigan astronomers examined old galaxies and were surprised to discover that they are still making new stars. The results provide insights into how galaxies evolve with time. U-M research fellow Alyson Ford and astronomy professor Joel Bregman presented their findings May 31 at a meeting of the Canadian Astronomical Society in London, Ontario. Using the Wide Field Camera 3 on the Hubble Space Telescope, they saw individual young stars and star clusters in four galaxies that...

2011-05-19 10:08:00

WASHINGTON, May 19, 2011 /PRNewswire-USNewswire/ -- A five-year survey of 200,000 galaxies, stretching back seven billion years in cosmic time, has led to one of the best independent confirmations that dark energy is driving our universe apart at accelerating speeds. (Logo: http://photos.prnewswire.com/prnh/20081007/38461LOGO) The survey used data from NASA's space-based Galaxy Evolution Explorer and the Anglo-Australian Telescope on Siding Spring Mountain in Australia. The findings...

2011-05-19 11:55:00

According to NASA, dark energy is driving our universe apart at an accelerated rate. Scientists performed a five-year survey of 200,000 galaxies to help add more evidence to the favored theory of how dark energy works.  This theory says dark energy works as a constant force, uniformly affecting the universe and propelling its runaway expansion.  "The action of dark energy is as if you threw a ball up in the air, and it kept speeding upward into the sky faster and faster," Chris...

Latest Galaxy formation and evolution Reference Libraries

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...

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...

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...

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...

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...

More Articles (9 articles) »
Word of the Day
  • A unit of saved energy.
Coined by Amory Lovins, chairman of the Rocky Mountain Institute as a contraction of negative watt on the model of similar compounds like megawatt.