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A new wider view of two very well-known galaxies has revealed a big surprise: They are connected by faint, starless filaments of hydrogen gas which trace back to a very high-speed intergalactic collision. The smash-up between galaxies M86 and NGC4438 not been suspected before, and may explain why M86, which is visible to the naked eye, is unable to give birth to new stars... During galactic smash-ups stars rarely collide, since there is so much space between them. But gases do slam into gases. The faster the collision, the higher the temperature the gases reach. In the case of M86,...

The standard model of cosmology predicts that the universe is infinite and flat. However, cosmologists in France and the US are now suggesting that space could be finite and shaped like a dodecahedron instead. They claim that a universe with the same shape as the twelve-sided polygon can explain measurements of the cosmic microwave background – the radiation left over from the big bang – that spaces with more mundane shapes cannot.Power spectrum of the cosmic microwave background (CMB) radiation. Data from WMAP have extended the accuracy of the spectrum far beyond what was known from earlier measurements. This plot...

Don't get the idea that we've found every kind of astronomical object there is in the universe. In a paper to appear in the Astrophysical Journal, astronomers working on the Supernova Cosmology Project report finding a new kind of something that they cannot make any sense of. Now you don't see it, now you do. Something in Bootes truly in the middle of nowhere — apparently not even in a galaxy — brightened by at least 120 times during more than three months and then faded away. Its spectrum was like nothing ever seen, write the discoverers, with "five broad...

CHICAGO (Reuters) - A Dutch primary school teacher and amateur astronomer has discovered what some are calling a "cosmic ghost," a strange, gaseous object with a hole in the middle that may represent a new class of astronomical object. The teacher, Hanny van Arkel, discovered the object while volunteering in the Galaxy Zoo project, which enlists the help of members of the public to classify galaxies online. "At first, we had no idea what it was. It could have been in our solar system, or at the edge of the universe," Yale University astrophysicist Kevin Schawinski, a member and co-founder...

Colorful Mystery Here's a new, truer-color rendering of the Voorwerp (lower center). Although it looked blue on the Sloan photo, the object actually now appears to be fairly green, observes Keel, who performed spectral analses of the huge mystery cloud.W. Keel Nearly a year ago, astronomers at several universities recruited citizen scientists to help them catalog distant galaxies that had recently been photographed as part of the Sloan Digital Sky Survey. A high-school physics teacher in the Netherlands who was participating in this project, known as Galaxy Zoo, appears to have scored a major coup. She brought a weird blue...

Baffled by the expansion of the universe? You're not alone. Even astronomers frequently get it wrong. The expansion of the universe may be the most important fact we have ever discovered about our origins. You would not be reading this article if the universe had not expanded. Human beings would not exist. Cold molecular things such as life-forms and terrestrial planets could not have come into existence unless the universe, starting from a hot big bang, had expanded and cooled. The formation of all the structures in the universe, from galaxies and stars to planets and Scientific American articles, has...

An x-ray pulsar pulls matter from its stellar companion. Artistic rendition: NASA/Dana Berry May 26, 2008 Predictions, Falsifiability and the Standard Model of Stellar EvolutionNew information about an odd pair of stars has contradicted the expectations of astronomers and called into question the Standard Model.Several Thunderbolts Pictures of the Day articles have covered the topics of variable stars, neutron stars and magnetars from the standpoints of electrical engineering and plasma physics. Reports have repeatedly demonstrated the surprise and bewilderment exhibited by astronomers at heavenly objects that have defied various theoretical expectations.Now it seems that the discovery of a pulsar...

picture of the day             archive             subject index           Solar flare seen through a hydrogen-alpha filter. Credit: Big Bear Solar Observatory May 23, 2008 Colossal Flare Erupts from EV LacertaeAn explosion thousands of times greater than anything seen on our Sun has been detected bursting from a neighboring star. In a March 19, 2008 press release, NASA officials from the Goddard Space Flight Center announced that their SWIFT satellite detected a stellar flare with x-ray emissions larger than anything they expected to witness from...

Hoag’s Object glares balefully across the light-years. Credit: Hubble Heritage May 19, 2008 Is Hoag’s Object a Dense Plasma Focus? What force swept away the stars and formed this 120,000 light-year-wide ring in space? This could be one of electrical energy’s protean forms.There are places in the cosmos where stars form up into ranks that stretch in lines for thousands of light-years. Elsewhere, rings of stars can be found encircling compact structures that have been measured at over 10,000 light-years in diameter.Art Hoag discovered the galaxy that bears his name in 1950 and by conventional redshift-equals-distance calculations, it is approximately...

Credit: NASA/JPL-Caltech Mar 03, 2008Mira: The Tale of a Giant StarThe light-years long plume of ionized gas from this red giant star provides evidence suggesting its electrical nature.NASA launched the Galaxy Evolution Explorer (GALEX) spacecraft on April 28, 2003 from the Cape Canaveral launch facility in southern Florida. Equipped with advanced near and ultraviolet detectors, GALEX was scheduled to remain in orbit for about 29 months studying galaxies in the hundreds of thousands. The mission has been extended and GALEX continues to return images such as the one of Mira, a red-giant star with a trail of material extending from...

A new study using results from NASA's Chandra X-ray Observatory provides one of the best pieces of evidence yet that many supermassive black holes are spinning extremely rapidly. The whirling of these giant black holes drives powerful jets that pump huge amounts of energy into their environment and affects galaxy growth. A team of scientists compared leading theories of jets produced by rotating supermassive black holes with Chandra data. A sampling of nine giant galaxies that exhibit large disturbances in their gaseous atmospheres showed that the central black holes in these galaxies must be spinning at near their maximum rates....

CHICAGO (AFP) - Hundreds of rogue black holes may be roaming around the Milky Way waiting to engulf stars and planets that cross their path, US astronomers said Wednesday. The astronomers believe these "intermediate mass" black holes are invisible except in rare circumstances and have been spawned by mergers of black holes within globular clusters -- swarms of stars held together by their mutual gravity. These black holes are unlikely to pose a threat to Earth, but may engulf nebulae, stars and planets that stray into their paths, the researchers said. "These rogue black holes are extremely unlikely to do...

The quasar OJ287 contains two black holes (this slightly dated illustration lists the larger black hole's mass as 17 billion Suns, though researchers now estimate it is 18 billion Suns). The smaller black hole crashes through a disc of material around the larger one twice every orbit, creating bright outbursts (Illustration: VISPA) The most massive known black hole in the universe has been discovered, weighing in with the mass of 18 billion Suns. Observing the orbit of a smaller black hole around this monster has allowed astronomers to test Einstein's theory of general relativity with stronger gravitational fields than ever...

WASHINGTON - The latest act of senseless violence caught on tape is cosmic in scope: A black hole in a "death star galaxy" blasting a neighboring galaxy with a deadly jet of radiation and energy. A fleet of space and ground telescopes have captured images of this cosmic violence, which people have never witnessed before, according to a new study released Monday by NASA. "It's like a bully, a black-hole bully punching the nose of a passing galaxy," said astrophysicist Neil deGrasse Tyson, director of the Hayden Planetarium in New York, who wasn't involved in the research. But ultimately, this...

Long before our solar system formed and even before the Milky Way assumed its final spiral shape, a star slightly smaller than the Sun blazed into life in our galaxy, formed from the newly scattered remains of the first stars in the universe. Employing techniques similar to those used to date archeological remains here on Earth, scientists have learned that a metal-poor star in our Milky Way called HE 1523 is 13.2 billion years old-just slightly younger than 13.7 billion year age of the universe. Our solar system is estimated to be only about 4.6 billion years old. The findings...

A project aiming to create an easier way to measure cosmic distances has instead turned up surprising evidence that our large and ancient universe might be even bigger and older than previously thought. If accurate, the finding would be difficult to mesh with current thinking about how the universe evolved, one scientist said. A research team led by Alceste Bonanos at the Carnegie Institution of Washington has found that the Triangulum Galaxy, also known as M33, is about 15 percent farther away from our own Milky Way than previously calculated. The finding, which will be detailed in an upcoming issue...

HAVE we hastened the demise of the universe by looking at it? That’s the startling question posed by a pair of physicists, who suggest that we may have accidentally nudged the universe closer to its death by observing dark energy, which is thought to be speeding up cosmic expansion. Lawrence Krauss of Case Western Reserve University in Cleveland, Ohio, and colleague James Dent suggest that by making this observation in 1998 we may have caused the universe to revert to a state similar to early in its history, when it was more likely to end. “Incredible as it seems, our...

These supermassive entities are known as high-energy quasars. These are a type of black hole, found in young galaxies, that are surrounded by a thick halo of gas and dust, which produces X-rays as it is sucked into the void. The presence of X-rays, even when the quasars themselves cannot be seen, is what tipped off the scientists to the fact they had stumbled across something extraordinary... The newfound quasars will help answer fundamental questions about how massive galaxies evolve. Astronomers now know, for example, that most of these galaxies steadily generate stars and black holes simultaneously until the latter...

NEW YORK - The Hubble Space Telescope has shown that a mysterious form of energy first conceived by Albert Einstein, then rejected by the famous physicist as his "greatest blunder," appears to have been fueling the expansion of the universe for most of its history. This so-called "dark energy" has been pushing the universe outward for at least 9 billion years, astronomers said Thursday. "This is the first time we have significant, discrete data from back then," said Adam Riess, a professor of astronomy at Johns Hopkins University and researcher at NASA's Space Telescope Science Institute. He and several colleagues...

An international team of astronomers has discovered within the heart of a nearby spiral galaxy a quasar whose light spectrum indicates that it is billions of light years away. The finding poses a cosmic puzzle: How could a galaxy 300 million light years away contain a stellar object several billion light years away? The team’s findings, which were presented today in San Diego at the January meeting of the American Astronomical Society and which will appear in the February 10 issue of the Astrophysical Journal, raise a fundamental problem for astronomers who had long assumed that the “high redshifts” in...

The result of the measurements, the team reports in an upcoming issue of The Astrophysical Journal, is that the nebula is only 1270 light-years away, or about 20&percent; closer than previous estimates. "We were surprised by the new distance, although in retrospect, we shouldn't be," says astronomer and co-author Geoffrey Bower. The new measurement fits with previous estimates when their margin of error is considered, he says. Because distance measurements are used to calculate the brightness--and hence age--of stars, the new data indicate that Orion's stars are older than previously thought, which makes them consistent with current theory about stellar...

Astronomers had identified I Zwicky 18 as one of the youngest galaxies in the universe. But Hubble astronomers have discovered it is, in fact, much older and farther away from Earth than thought... Hubble has found fainter older red stars contained within the galaxy, suggesting its star formation started at least 1 billion years ago and possibly as much as 10 billion years ago... also suggests I Zwicky 18 is 59 million light-years from Earth, nearly 10 million light-years more distant than believed.

An international team of astronomers have conclusive new evidence that a recently discovered "dark galaxy" is, in fact, an object the size of a galaxy, made entirely of dark matter. Although the object, named VIRGOHI21, has been observed since 2000, astronomers have been slowly ruling out every alternative explanation. In a new research paper, entitled 21-cm synthesis observations of VIRGOHI 21 – a possible dark galaxy in the Virgo Cluster, researchers provide updated evidence about this mysterious galaxy. They have now performed a high resolution observations of VIRGOHI21 using the Westerbork Synthesis Radio Telescope (WSRT), to better pin down the...

MELBOURNE, Fla.—Eric Perlman, Florida Tech associate professor of physics and space sciences, has earned $490,400 in funding over three years from NASA’s Long-term Space Astrophysics grant program. The program supports long-term research projects in astronomy and astrophysics. Perlman will conduct observational and theoretical work on jets, which are energetic outflows from the centers of some bright galaxies. They emerge typically from the regions immediately surrounding the central black hole, with a velocity nearly equal to the speed of light. His project title is, “Probing the Basic Physics of Extragalactic Jets.” “The jets are the largest, most powerful particle accelerators in...

In a cascade of superlatives that belies the traditional cerebral reserve of their profession, astronomers reported Monday that they had seen the brightest and most powerful stellar explosion ever recorded. The cataclysm - a monster more than a hundred times as energetic as the typical supernova in which normal massive stars end their lives - may be an example, they said, of a completely new type of explosion. Such a blast, proposed but never seen, would explain how the earliest and most massive stars in the universe ended their lives and strewed new elements across space to fertilize future stars...

Astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) have announced that they have found the most massive known transiting extrasolar planet. The gas giant planet, called HAT-P-2b, contains more than eight times the mass of Jupiter, the biggest planet in our solar system. Its powerful gravity squashes it into a ball only slightly larger than Jupiter. HAT-P-2b shows other unusual characteristics. It has an extremely oval orbit that brings it as close as 3.1 million miles from its star before swinging three times farther out, to a distance of 9.6 million miles. If Earth's orbit were as elliptical, we would...

A giant cloud of superheated gas 6 million light years wide might be formed by the collective sigh of several supermassive black holes, scientists say. The plasma cloud, detailed in April 10 issue of Astrophysical Journal, might be the source of mysterious cosmic rays that permeate our universe. “One of the most exciting aspects of the discovery is the new questions it poses,” said study leader Philipp Kronberg of Los Alamos National Laboratories in New Mexico. “For example, what kind of mechanism could create a cloud of such enormous dimensions that does not coincide with any single galaxy or galaxy...

Attempts to measure the size, age, and “expansion” of the universe may be a good deal less precise than advertised. But the problem is much worse if the astronomers’ assumptions are incorrect. An astronomer at Ohio State University, using a new method that is independent of the Hubble relation (which relates redshift to distance), has determined that the Hubble constant (the rate at which the universe is expanding) is 15% lower than the accepted value. His measurements have a margin of error of 6%. To “determine the Hubble constant” these six galaxy clusters are a subset of the 38 that...

This false-color composite of the triple quasar system was made using a combination of Keck Observatory's and the European Very Large Telescope's visible and infrared data. S. G. Djorgovski and colleagues, Caltech, and EPFLOf all the known objects known in the universe, quasars probably deserves the most superlatives. These blazing cosmic beacons pack the energy of an entire galaxy’s worth of stars into a volume of space the size of our solar system. Until now, astronomers have found about 100,000 of these extraordinary objects, which are fueled by supermassive black holes devouring large clumps of matter. Most quasars are solitary...

WASHINGTON - The largest planet ever found orbiting another star is so puffy it would float on water, astronomers said Thursday. The newly discovered planet, dubbed HAT-P-1, is both the largest and least dense of the nearly 200 worlds astronomers have found outside our own solar system. HAT-P-1 orbits one of a pair of stars in the constellation Lacerta, about 450 light-years from Earth. "This new planet, if you could imagine putting it in a cosmic water glass, it would float," said Robert Noyes, a research astrophysicist with the Smithsonian Astrophysical Observatory. HAT-P-1 is an oddball planet, since it orbits...

When Douglas Clowe of the University of Arizona in Tucson announced on 21 August that his team had "direct proof of dark matter's existence", it seemed the issue had been settled. Now proponents of the so-called modified theories of gravity, who explain the motion of stars and galaxies without resorting to dark matter, have hit back and are suggesting that Clowe's team has jumped the gun. "One should not draw premature conclusions about the existence of dark matter without a careful analysis of alternative gravity theories," writes John Moffat, of the University of Waterloo in Ontario, Canada, who pioneered an...

MOON DAILYBig Bang Afterglow Fails An Intergalactic Shadow Test Because it is seen coming from every direction in nearly uniform power and frequency, cosmologists theorized that the microwave background is afterglow radiation left over by the Big Bang that created the universe. by Staff Writers Huntsville AL (SPX) Sep 03, 2006 The apparent absence of shadows where shadows were expected to be is raising new questions about the faint glow of microwave radiation once hailed as proof that the universe was created by a "Big Bang." In a finding sure to cause controversy, scientists at The University of Alabama in...

A star in a galaxy about 440 million light-years away released in a few seconds more energy than the sun will over the course of its entire lifetime, according to observations made on February 18. A high-energy jet of x-rays shot out from the doomed star's core and was captured by the Burst Alert Telescope on NASA's Swift satellite. The satellite relayed the information to astronomers on the ground, and within days a wide array of telescopes turned to the exploding object. Meanwhile the other telescopes on Swift continued to observe the unusually long-lived burst; it lasted 40 minutes compared...

A controversial alternative to black hole theory has been bolstered by observations of an object in the distant universe, researchers say. If their interpretation is correct, it might mean black holes do not exist and are in fact bizarre and compact balls of plasma called MECOs. Rudolph Schild of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, US, led a team that observed a quasar situated 9 billion light years from Earth. A quasar is a very bright, compact object, whose radiation is usually thought to be generated by a giant black hole devouring its surrounding matter. A rare cosmological...

How an alternate theory of the universe exposes the 'war of words' that underlies modern cosmology. Theoretical physicists have recently been frustrated by a bold hypothesis concerning black holes—specifically, that they don't exist. In March, at the 22nd Pacific Coast Gravity Meeting in Santa Barbara, Calif., George Chapline, an applied physicist at Lawrence Livermore National Laboratory, gave a talk based on ideas he's been incubating for several years. His goal: to amend astrophysics by applying theories of dark energy and condensed matter physics. His work reinvents black holes as so-called "dark energy stars," which are what is left over when...

Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies. The discovery, using NASA's Chandra X-ray Observatory and other telescopes, gives direct evidence for the existence of dark matter. "This is the most energetic cosmic event, besides the Big Bang, which we know about," said team member Maxim Markevitch of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. These observations provide the strongest evidence yet that most of the matter in the universe is dark. Despite considerable evidence for dark matter, some scientists have proposed alternative theories for gravity where it...

The pulsar B1508+55, about 7700 light-years from Earth, is speeding away from our Galaxy to an unknown Galaxy. Scientists are perplexed with the speed at which this speeding, superdense neutron star is moving... Its discovery is puzzling astronomers who used the National Science Foundation's Very Long Baseline Array (VLBA) radio telescope to directly measure the fastest speed yet found in a neutron star... "We know that supernova explosions can give a kick to the resulting neutron star, but the tremendous speed of this object pushes the limits of our current understanding," said Shami Chatterjee last year, of the National Radio...

Is the Universe older than expected? 10 July 2002 An analysis of 13.5 thousand million-year-old X-rays, captured by ESA’s XMM-Newton satellite, has shown that either the Universe may be older than astronomers had thought or that mysterious, undiscovered ‘iron factories’ litter the early Universe. ESA's Norbert Schartel and colleagues from the Max-Planck-Institut für extraterrestrische Physik,Germany, found more iron than anyone thought possible in the extremely distant celestial object, APM 8279+5255. The object is a quasar, that is, a young galaxy containing an incredibly bright central region, caused by gas falling into a giant black hole. APM 8279+5255 is 13.5...

A handful of researchers posit an alternative theory of origin — the universe has no beginning Many, if not most, people assume that certain aspects of nature’s workings are absolutely known. Outside of intelligent design circles, no modern biologist doubts the theory of evolution by natural selection; it is too well established by harmonious data across a multiplicity of fields. No credible doctor questions the germ theory of disease. And, one might think, no serious cosmologist disagrees with the standard cosmological model. The SCM is the official designation of what is informally called “the big bang�: that relatively recent but...

Astronomers who think they know how the very early universe came to have so much interstellar dust need to think again, according to new results from the Spitzer Space Telescope. In the last few years, observers have discovered huge quantities of interstellar dust near the most distant quasars in the very young universe, only 700 million years after the cosmos was born in the Big Bang. "And that becomes a big question," said Oliver Krause of the University of Arizona Steward Observatory in Tucson and the Max Planck Institute for Astronomy in Heidelberg. "How could all of this dust have...

A new analysis of 'cool' spots in the cosmic microwave background may cast new doubts on a key piece of evidence supporting the big bang theory of how the universe was formed. Two scientists at The University of Alabama in Huntsville (UAH) looked for but couldn't find evidence of gravitational "lensing" where you might expect to find it, in the most distant light source in the universe -- the cosmic microwave background. Results of this research by Dr. Richard Lieu, a UAH physics professor, and Dr. Jonathan Mittaz, a UAH research associate, were published Monday in the "Astrophysical Journal." In...

Crisis in the Cosmos?Galaxy-formation theory is in peril Ron Cowen Imagine peering into a nursery and seeing, among the cooing babies, a few that look like grown men. That's the startling situation that astronomers have stumbled upon as they've looked deep into space and thus back to a time when newborn galaxies filled the cosmos. Some of these babies have turned out to be nearly as massive as the Milky Way and other galactic geezers that have taken billions of years to form. Despite being only about 800 million years old, some of the infants are chock-full of old stars....

Public confidence in the "constants" of nature may be at an all time low. Recent research has found evidence that the value of certain fundamental parameters, such as the speed of light or the invisible glue that holds nuclei together, may have been different in the past. "There is absolutely no reason these constants should be constant," says astronomer Michael Murphy of the University of Cambridge. "These are famous numbers in physics, but we have no real reason for why they are what they are." The observed differences are small—roughly a few parts in a million—but the implications are huge:...

Enigmatic object baffles supernova team 13:15 19 June 2006 NewScientist.com news service Jeff Hecht An astronomical enigma has been spotted by a team hunting for very distant supernovas for their studies of the early universe. At first glance, the object discovered on 22 February in the constellation Bootes resembled an ordinary supernova. But it kept growing brighter for much too long, and its spectrum was abnormal. The mysterious object was spotted by the Hubble Space Telescope's Advanced Camera for Surveys and took at least 100 days to reach peak brightness, says Kyle Dawson of the Lawrence Berkeley National Laboratory in...

Most Powerful Eruption in the Universe Discovered Astronomers have found the most powerful eruption in the universe using NASA's Chandra X-ray Observatory. A super massive black hole generated this eruption by growing at a remarkable rate. This discovery shows the enormous appetite of large black holes, and the profound impact they have on their surroundings. The huge eruption was seen in a Chandra image of the hot, X-ray emitting gas of a galaxy cluster called MS 0735.6+7421. Two vast cavities extend away from the super massive black hole in the cluster's central galaxy. The eruption, which has lasted for...

JAMES REYNOLDS SCIENCE CORRESPONDENT AMATEUR radio hams are usually excited by the faint buzz of a distant shortwave station, but a group of scientists believe they have received a message from extra-terrestrials. Astronomers think that a signal picked up by a radio telescope last year shows the highest probability yet that ET’s family may have returned his call. In February 2003, scientists involved in the search for extra-terrestrial intelligence (SETI) pointed the huge radio telescope in Arecibo, Puerto Rico, at about 200 sections of the sky. Unexplained radio signals had been detected twice by the same telescope in these areas...

    Mysterious signals from 1000 light years away   19:00 01 September 04     In February 2003, astronomers involved in the search for extraterrestrial intelligence (SETI) pointed the massive radio telescope in Arecibo, Puerto Rico, at around 200 sections of the sky. The same telescope had previously detected unexplained radio signals at least twice from each of these regions, and the astronomers were trying to reconfirm the findings. The team has now finished analysing the data, and all the signals seem to have disappeared. Except one, which has got stronger. This radio signal, now seen on three separate occasions, is...

BERKELEY – A University of California, Berkeley, astronomer has turned the NASA Hubble Space Telescope on the brightest and nearest supernova of the past decade, capturing a massive stellar explosion blazing with the light of 200 million suns. The supernova, called SN 2004dj, is so bright in the Hubble image that it easily could be mistaken for a foreground star in our Milky Way Galaxy. Yet it lies 11 million light-years from Earth in the outskirts of a galaxy called NGC 2403, nestled in a cluster of mostly massive bright blue stars only 14 million years old. "This has to...