Latest Dark matter Stories

2011-07-21 08:20:00

The Andromeda Galaxy is revealed in unprecedented detail in four archive observations from the NASA/ESA Hubble Space Telescope. They show stars and structure in the galaxy's disc, the halo of stars that surrounds it, and a stream of stars left by a companion galaxy as it was torn apart and pulled in by the galaxy's gravitational forces. These four observations made by Hubble's Advanced Camera for Surveys give a close up view of the Andromeda Galaxy, also known as Messier 31 (M 31)....

2011-07-14 07:32:42

Simulations improve characterization of cosmology's "Ëœstandard ruler' Ohio State University researchers are leveraging powerful supercomputers to investigate one of the key observational probes of "dark energy," the mysterious energy form that is causing the expansion of the universe to accelerate over time. The OSU project, led by Chris Orban, a graduate research fellow in physics at Ohio State's Center for Cosmology and Astro-Particle Physics, focuses on simulations created on...

2011-07-14 06:25:00

White dwarfs are the burned-out cores of stars like our Sun. Astronomers have discovered a pair of white dwarfs spiraling into one another at breakneck speeds. Today, these white dwarfs are so near they make a complete orbit in just 13 minutes, but they are gradually slipping closer together. About 900,000 years from now - a blink of an eye in astronomical time - they will merge and possibly explode as a supernova. By watching the stars converge, scientists will test both Einstein's general...

2011-07-13 06:35:00

A new study combining data from ESO's Very Large Telescope and ESA's XMM-Newton X-ray space observatory has turned up a surprise. Most of the huge black holes in the centers of galaxies in the past 11 billion years were not turned on by mergers between galaxies, as had been previously thought. At the heart of most, if not all, large galaxies lurks a supermassive black hole with a mass millions, or sometimes billions, times greater than that of the Sun. In many galaxies, including our own...

2011-07-02 07:07:57

Galaxies once thought of as voracious tigers are more like grazing cows, according to a new study using NASA's Spitzer Space Telescope. Astronomers have discovered that galaxies in the distant, early universe continuously ingested their star-making fuel over long periods of time. This goes against previous theories that the galaxies devoured their fuel in quick bursts after run-ins with other galaxies. "Our study shows the merging of massive galaxies was not the dominant method of galaxy...

2011-07-01 06:10:00

Astronomers are puzzled by the announcement that the masses of the largest objects in the Universe appear to depend on which method is used to weigh them. The new work was presented at a specialist discussion meeting on 'Scaling Relations of Galaxy Clusters' organized by the Astrophysics Research Institute (ARI) at Liverpool John Moores University and supported by the Royal Astronomical Society. Clusters of galaxies are the largest gravitationally bound objects in the Universe containing...

2011-06-29 07:57:42

Gravitational Lensing by Clusters of Galaxies Yet another independent line of evidence points to the dominance of dark matter in galaxy clusters. According to Einstein's theory of general relativity, space is curved in the vicinity of strong gravitational fields. One consequence of the warping of space by gravity is that the path of light from background galaxies is bent when it passes near a cluster, in much the same way that a glass lens will bend light. The images of the galaxies are...

2011-06-22 09:45:00

A team of scientists has studied the galaxy cluster Abell 2744, nicknamed Pandora's Cluster. They have pieced together the cluster's complex and violent history using telescopes in space and on the ground, including ESO's Very Large Telescope and the Hubble Space Telescope. Abell 2744 seems to be the result of a simultaneous pile-up of at least four separate galaxy clusters and this complex collision has produced strange effects that have never been seen together before. When huge clusters of...

2011-06-17 08:47:40

An international research team led by Japan and that includes the University of Colorado Boulder may have taken a significant step in discovering why matter trumped antimatter at the time of Big Bang, helping to create virtually all of the galaxies and stars in the universe. The experiment, known as the Tokai to Kamioka experiment, or T2K, included shooting a beam of neutrinos underground from the Japan Proton Accelerator Research Complex, or J-PARC, on the country's east coast to a detector...

2011-06-13 14:22:44

Portrayed in movies and on television most often as gateways to another dimension or cosmic vacuum cleaners sucking up everything in sight, the misconceptions surrounding black holes are many and varied. In reality, black holes form when, at the end of their life cycle, heavy stars collapse into a supernova. After a black hole forms, it can continue to grow by absorbing its surroundings. By absorbing other stars and merging with other black holes, giant black holes -- called supermassive --...

Latest Dark matter Reference Libraries

2014-01-12 00:00:00

Image Caption: The Hubble Extreme Deep Field (XDF) was completed in September 2012 and shows the farthest galaxies ever photographed by humans. Each speck of light in the photo is an individual galaxy, some of them as old as 13.2 billion years; the observable universe is estimated to contain more than 200 billion galaxies. Credit: NASA/Wikipedia What is Cosmology? I once commented to an acquaintance that I was fascinated by the field of Cosmology, and mused that if I had more time, I...

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 17:31:13

The Bullet Cluster is made up of two colliding clusters galaxies. According to a 2006 study, the Bullet Cluster also shows the best evidence for the existence of Dark Matter. From observations of galaxy cluster collisions it has been found that many show displacement between their center of visible matter and their gravitational potential. Each component, stars, gas, and dark matter, within a cluster pair behaves differently during a collision allowing for each to be studied separately....

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...

2010-09-13 16:46:47

The cluster CL0024+17, located in Pisces, is a galaxy cluster that is allowing astronomers to probe the distribution of dark matter in space. Dark matter does not reflect light and therefore cannot be seen. It is only detectable by the way its gravity affects the lights around it. Using gravitational lensing astronomers observe the distorted light around the dark matter and are able to tell where it is located within a cluster. A dark matter ring found near the cluster's center, by...

More Articles (13 articles) »
Word of the Day
  • A fudgelike confection of brown sugar, cream or milk, and chopped nuts.
'Penuche' is a variant of 'panocha,' a coarse grade of sugar made in Mexico. 'Panocha' probably comes from the Spanish 'panoja, panocha,' ear of grain.