Free Republic

The mystery behind the power source of the giant "Lyman-alpha blob," one of the largest single objects known in the universe, has finally been revealed by astronomers at the European Southern Observatory. Observations from ESO's Very Large Telescope have led to the conclusion that rare vast cloud of glowing gas from the earliest days of the universe must be powered by galaxies embedded within it. The results appear in the Aug. 18 issue of the journal Nature. Lyman-alpha blobs are huge gaseous structures emitting Lyman-alpha frequency light. Some of these are more than 400,000 light years across in size....

NASA has unveiled a flood of photos showing millions galaxies, stars and asteroids photographed by a prolific sky-mapping telescope that ended its mission earlier this year. For the first time, the space agency publicly released more than half of the 2.7 million images taken by its Wide-field Infrared Survey Explorer (WISE) telescope during its mission to map the entire sky. WISE launched in December 2009 and spent 14 months scanning the heavens in infrared light before shutting down this past February. The $320 million space telescope hunted for asteroids and comets, as well as more distant cosmic objects revealed by...

“Just as a fish may be barely aware of the medium in which it lives and swims, so the microstructure of empty space could be far too complex for unaided human brains." -- Sir Martin Rees, Astronomer Royal, physicist, Cambridge University Our known Hubble length universe contains hundreds of millions of galaxies that have clumped together, forming super clusters and a series of massive walls of galaxies separated by vast voids of empty space. Great Wall: The most vast structure ever is a collection of superclusters a billion light years away extending for 5% the length of the entire observable...

Image of the Day: Galaxies Beyond Comprehension (and Seven-Trillion Dwarfs!)   ESA’s Herschel space telescope has discovered that previously unseen distant galaxies are responsible for a cosmic fog of infrared radiation. The galaxies are some of the faintest and furthest objects seen by Herschel, and open a new window on the birth of stars in the early Universe. Astronomers estimate that their are billions and billions of galaxies in the observable universe (as well as some seven trillion dwarf galaxies) . Here's the breakout of the visible universe within 14 billion light years: Superclusters in the visible universe =...

A Deep-Sky Look at Lensing by Paul Gilster on January 13, 2011 As we continue to investigate the parameters of the proposed FOCAL mission to the SunÂ’s gravitational lens, itÂ’s worth recalling how the idea of lensing has taken hold in recent decades. Einstein noted the possibilities of such lensing as far back as 1936, but it wasnÂ’t until 1964 that Sydney Liebes (Stanford University) worked out the mathematical theory, explaining how a galaxy between the Earth and an extremely distant object like a quasar could focus the latterÂ’s light in ways that should be detectable by astronomers. And...

Displayed in all their exquisite detail, six spectacular galaxies are pictured more clearly that they ever have before. All of them are beautiful examples of spiral galaxies and were captured in images from ESO’s Very Large Telescope (VLT) at the Paranal Observatory in Chile. The pictures were taken in infrared light, using the impressive power of the HAWK-I camera, and will help astronomers understand how the remarkable spiral patterns in galaxies form and evolve.-incredible-new-detail.html#ixzz13uAfNijg

Armchair astronomers have helped discover a batch of tiny galaxies that may help professional astronomers understand how galaxies formed stars in the early universe. Dubbed the "Green Peas," the galaxies are forming stars 10 times faster then the Milky Way despite being 10 times smaller and 100 times less massive. They are between 1.5 billion and 5 billion light years away "These are among the most extremely active star-forming galaxies we've ever found," said Carolin Cardamone, lead author of a paper on the discoveries to be published in an upcoming issue of the Monthly Notices of the Royal Astronomical Society....

A 10-year study of 100,000 galaxies close to our own offers compelling proof that long-hypothesized "dark matter" does exist and is in fact a guiding force behind the structure of the universe, a team of Australian, British, and American astronomers revealed this week. Saying that "the universe we see is really quite structured," one of the lead researchers explained that the 10-year "census" of galaxies near our own Milky Way offers powerful evidence that this invisible dark matter "seems to hold the galaxies together." The dark matter's influence on galaxies "stops their constituent stars from flying off and it seems...

A detailed analysis of eight dwarf galaxies that orbit the Milky Way indicates that their orbital behaviour can be explained more accurately with Modified Newtonian Dynamics (MOND) than by the rival, but more widely accepted, theory of dark matter. The results were presented by Garry Angus, of the University of St Andrews, at the RAS National Astronomy Meeting in Belfast on Wednesday 2nd April. 'MOND was first suggested to account for things that we see in the distant universe. This is the first detailed study in which we've been able to test out the theory on something close to home....

Perfectly Aligned Galaxies Found For the First Time John Roach for National Geographic NewsJanuary 11, 2008 Astronomers have found three galaxies in a never before seen perfect alignment—a discovery that may help scientists better understand the mysterious dark matter and dark energy believed to dominate the universe. The three galaxies are like beads on a string, one directly behind the other, scientists announced yesterday at a meeting of the American Astronomical Society in Austin, Texas. This makes the massive galaxy closest to Earth appear nestled in a pair of circular halos known as Einstein rings. The phenomenon occurs because the...

LONDON - Young galaxies, so faint that scientists struggled to prove they were there at all, have been discovered by aiming two of the world's most powerful telescopes at a single patch of sky for nearly 100 hours. An international group of researchers has identified 27 pre-galactic fragments, dubbed "teenager galaxies," which they hope will help astronomers understand how our own Milky Way reached adulthood. Cambridge University scientist Martin Haehnelt said his team used the European Southern Observatory's Very Large Telescope and the Gemini Telescope in Chile to monitor a section of the universe for 92 hours — the equivalent...

Black holes often are thought of as just endless pits in space and time that destroy everything they pull toward them. But new findings confirm the reverse is true, too: Black holes can drive extraordinarily powerful winds that push out and force star formation and shape the fate of a galaxy. Supermassive black holes are suspected to lurk in the hearts of many—if not all—large galaxies. These holes drag gas inward, which accrues in rapidly spinning, glowing disks. Astronomers have long thought that such "accretion disks" give off mighty winds that shape the host galaxies, profoundly influencing how they grow....

ROME (CNS) -- The Vatican Observatory called together some of the world's top astronomers for a major conference on the creation and evolution of disk galaxies in an effort to better understand the nature of the universe. More than 200 men and women from 26 countries attended the Oct. 1-5 conference in Rome to share some of the discoveries since the Vatican's last galaxy conference in 2000. The observatory director, Argentine Jesuit Father Jose Funes, said they were able to attract top scientists and scholars for the meeting because "the Vatican Observatory is a prestigious institute, and the Holy See...

I have studied a sample of 200,000 elliptical galaxies with redshifts <0.20 from the Sloan Digital Sky Survey (SDSS) to investigate whether they tend to have their ellipticities aligned along a particular axis. The data show a 13 standard deviation signal for such an alignment. The axis is close to the spiral spin axis found previously and to that of the quadrupole and octopole moments in the WMAP microwave sky survey

Like gluttonous piranhas, supermassive black holes in young galaxy clusters gorge on bountiful gas until little fuel is left, and then they fade away, a new study suggests.Using NASA's Chandra X-ray Observatory, astronomers tallied the number of rapidly growing supermassive black holes, called active galactic nuclei, or AGN, in two populations of galaxy clusters. One group consisted of young-looking clusters located very far from Earth, and the other consisted of an older group located closer to us. The results of the survey, detailed in the July 20 issue of The Astrophysical Journal Letters, showed that the more distant, younger clusters...

Astronomers have found evidence for the most distant galaxies ever detected. The galaxies are seen as they existed just 500 million years after the birth of the universe. Their light, traversing the cosmos for more than 13 billion years, was seen only because it was distorted in a natural "gravitational lens" created by the gravity-bending mass of a nearer cluster of galaxies. "Gravitational lensing is the magnification of distant sources by foreground structures," explained Caltech astronomer Richard Ellis, who led the international team. "By looking through carefully selected clusters, we have located six star-forming galaxies seen at unprecedented distances, corresponding...

WASHINGTON (Reuters) - A seemingly violent collision of two galaxies is in fact a fertile marriage that has birthed billions of new stars, and an image released on Tuesday gives astronomers their best view yet. The new image of the Antennae galaxies allows astronomers working with the orbiting Hubble Space Telescope to distinguish between new stars and the star clusters that form them. Most of these clusters, created in the collision of the two galaxies, will disperse within 10 million years but about 100 of the largest will grow into "globular clusters" -- large groups of stars found in many...

An enormous amoeba-like structure 200 million light-years wide and made up of galaxies and large bubbles of gas is the largest known object in the universe, scientists say. The galaxies and gas bubbles, called Lyman alpha blobs, are aligned along three curvy filaments that formed about 2 billion years after the universe exploded into existence after the theoretical Big Bang. The filaments were recently seen using the Subaru and Keck telescopes on Mauna Kea. The galaxies within the newly found structure are packed together four times closer than the universe's average. Some of the gas bubbles are up to 400,000...

When the universe was young, countless dwarf galaxies formed, heating the universe and preventing the formation of more small galaxies, a new study suggests. The Big Bang, a theoretical beginning to the universe, is thought to have generated lots of hot stuff—electrons and hydrogen and helium ions. The material expanded rapidly. As space expanded, matter cooled, and the electrons and ions formed neutral atoms and absorbed surrounding light. This placed a dark curtain throughout space. The shadowy era is called the Dark Ages.

Astronomers have detected a faint halo of hot gas surrounding and falling into a spiral galaxy located 100 million light-years from Earth. The discovery provides a long-sought missing link in theories of galaxy formation and helps solve the riddle of where galaxies get the fuel they need to create new stars billions of years after they have already formed. "What we are likely witnessing here is the ongoing galaxy formation process," said study leader Kristian Pedersen of the University of Copehnhagen, Denmark. The spherical gas halo was found centered on the nucleus of NGC 5746, a spiral galaxy like our...