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They show the atmosphere of the white dwarf, says Pietsch. White dwarfs are hot stellar corpses left behind after the rest of the star has been ejected into space ... A typical white dwarf contains about the mass of the Sun, in a spherical volume little bigger than the Earth. (Science Daily)
NASA's Chandra Sees Brightest Supernova Ever May 9, 2007
The Chandra observation allowed the team to rule out the most likely alternative explanation for the supernova, namely that it was an explosion of a white dwarf star with a mass only slightly higher than the Sun into a dense, hydrogen-rich environment. In that event, SN 2006gy should have been 1,000 times brighter in X-rays than what Chandra detected. (Science Daily)
Exploded Star the Brightest Ever Seen May 9, 2007
Using the Chandra instruments, researchers were able to rule out the most likely alternative explanation for the huge supernova: that a white dwarf star with a mass about that of the sun exploded in a hydrogen-rich environment, leading to the unprecedented brightness. The Chandra instruments, however, found that the exploded star was not producing the X-ray radiation expected under those conditions. (Yahoo News -- Astronomy and Space)
The biggest bang of them all May 8, 2007
One possible explanation was that it was an exploding white dwarf a star of a mass similar to the Sun that has exhausted its nuclear fuel. But for an exploding white dwarf to produce that much light, the star would need to have interacted with other matter, such as a surrounding cloud of hydrogen. (Nature News Service)
Astronomers Report Biggest Stellar Explosion May 8, 2007
Supernovas come about in two basic ways: explosions of small stars about one and half times the mass of the Sun, known as White Dwarfs, and which are uniform enough to serve as cosmological distance markers; and the collapse of the cores of more massive stars into black holes or neutron stars when their thermonuclear fuel has run out. The astronomers first suspected that the supernovas dramatic output was caused by the shock wave of a white dwarf exploding into a dense cloud of hydrogen. (Yahoo News -- Astronomy and Space)
'Van Gogh' Simulations Give New Insight Into Turbulent Stars Apr 21, 2007
The swirling simulations, which are reminiscent of Van Gogh's star paintings, show the interior of a star during the Asymptotic Giant Branch (AGB) phase, the final stage of a low- and intermediate-mass star's life before it becomes a white dwarf. It is during this phase that many of the heavier elements, such as carbon and sodium, are created inside the stars. (Science Daily)
Hubble Space Telescope Reveals The Aftermath Of 'Star Wars' Apr 21, 2007
In this artist's impression of the binary star system RS Ophiuchi hydrogen-rich gas transferred from a red giant onto the surface of a white dwarf has just exploded ... RS Oph consists of a white dwarf, a super-dense dead star about the size of the Earth which was once the core of a star like the Sun and whose outer layers have been lost into space, in close orbit with a much larger, so-called red giant star ... The two stars are so close together that the strong gravitational field of the white... (Science Daily)
New thinking on the death of Sun-like stars Apr 9, 2007
Stars smaller than the Sun and up to eight times as massive die by swelling up into red giants before shedding most of their mass to shrink into very compact, dying embers called white dwarfs ... In the middle of the planetary haze the star's core looks like it has become a so-called white dwarf. (USA Today -- Tech)
Dust clouds in cosmic cycle Apr 5, 2007
Stars smaller than our sun and up to eight times as large die by first swelling up to being a red giant, and then shrinking to a white dwarf. There are two types of red giants, one contains lots of carbon and the the other a lot of oxygen. (EurekAlert!)
Flash team detonates white dwarf star in 3-D Mar 30, 2007
This simulation image shows an exploding white dwarf star ... University scientists are replicating nature s recipe for incinerating a white dwarf star ... White dwarf stars pack one and a half times the mass of the sun into an object the size of Earth. (Univeristy of Chicago Chronicle, IL)
Photo in the News: Star Explosion Highlights "Purple Rose of Virgo" Mar 30, 2007
Supernovas of this kind called Type 1a usually occur in binary systems, when a compact star called a white dwarf draws matter away from its companion. When it gains enough mass, the white dwarf collapses under the pressure setting off a cosmic fireworks show and sending matter hurtling off in excess of 9,300 miles (15,000 kilometers) a second. (National Geographic)
The Purple Rose Of Virgo: VLT Image of Bright Supernova in Spiral Galaxy Mar 29, 2007
A Type Ia supernova is thought to be the result of the explosion of a small and dense star - a white dwarf - inside a binary system. As its companion continuously spills matter onto the white dwarf, the white dwarf reaches a critical mass, leading to a fatal instability and the supernova. (Science Daily)
Scientists Compute Death Throes Of White Dwarf Star In 3D Mar 28, 2007
White dwarf stars pack one and a half times the mass of the sun into an object the size of Earth ... This image shows the last stage of an exploding white dwarf star ... Scientists for years have attempted to blow up a white dwarf star by writing the laws of physics into computer software and then testing it in simulations. (Science Daily)
Wow! Astronomers explode a virtual star Mar 23, 2007
March 22: A 3-D supercomputer simulation shows the first few seconds of a white dwarf star's destruction ... When their core furnace begins to burn out, white dwarfs explode in so-called Type 1a that astronomers say could be responsible for producing most of the iron in the universe ... With more tweaking of models, University of Chicago scientists generated natural detonations of white dwarf stars in simplified, two-dimensional simulations. (MSNBC -- Technology)
Massive explosion from tiny star system Mar 14, 2007
Classical novas, another subclass of cataclysmic variables, erupt due to a sudden but large dump of material from the red dwarf onto the white dwarf. The explosions, therefore, occur less frequently but with such vigor that they are up to a million times brighter than dwarf novas. (MSNBC -- Technology)
Double-star Systems Cycle Between Big And Small Blasts Mar 9, 2007
Astronomers have long known Z Cam to be a cataclysmic binary--a system that features a collapsed, dead star, or white dwarf, which sucks hydrogen-rich matter from its companion like a stellar vampire. The stolen material forms an orbiting disk of gas and dust around the white dwarf ... It brightens about 40-fold every 3 weeks or so, when an instability causes some of the material drawn by the white dwarf to crash onto its surface. (Science Daily)
Colorful Demise Of A Sun-like Star Mar 5, 2007
The burned-out star, called a white dwarf, is the white dot in the centre ... The white dwarf at the centre of NGC 2440 is one of the hottest known, with a surface temperature of more than 200,000 degrees Celsius. (Science Daily)
Variable Star Classifications Mar 3, 2007
Novae are explosions involving only the surface layers of a white dwarf star ... Type I supernovae occur when a white dwarf star exceeds the maximum mass limit of 1. (Suite101.com)
Scientists Make Explosive Discovery About Nature Of Supernovae Feb 26, 2007
Thermonuclear, or Type Ia, supernovae occur when a white dwarf star, which typically travels through space with a companion star that eventually leaks its own mass onto the dwarf, reaches its mass limit and explodes ... Reynolds and his team used the powerful Chandra X-ray telescope to observe the Kepler supernova, and they discovered that Kepler is something entirely new: a Type Ia supernova in which the progenitor of the white dwarf star that created it had enough mass to create circumstellar... (Science Daily)
Cosmic Lighthouses: Astrophysicists Explain Differences In Brightness Of Supernova Explosions Feb 24, 2007 Chili peppers on the menu for at least 6000 years Feb 19, 2007 A Dead Star's Dusty Ring Feb 19, 2007 End of the world - in close-up Feb 18, 2007 Week in Photos: Virgin Galactic, Huge Fish, Helix Nebula, More Feb 17, 2007 Parallel computing will allow Flash Center to complete 2.5 million hours of computer processing by next January Feb 16, 2007 Photo in the News: Hubble Spies Dazzling Death of a Sunlike Star Feb 15, 2007 Comet clash kicks up dusty haze Feb 15, 2007 NASA sends postcard from the future Feb 14, 2007 Universe Contains More Calcium Than Expected Feb 7, 2007 Earth's Moon Destined to Disintegrate Jan 23, 2007 REWINDING THE LAWS OF TIME AND SPACE Jan 22, 2007 Integral Sees The Galactic Centre Playing Hide And Seek Jan 19, 2007 AAS Supernova Roundup Jan 17, 2007 First Detection Of A Planet-Forming Disk Near Environment Of A Dying Star Jan 17, 2007 UCSC research on dark matter and supernovae supported Jan 15, 2007 News from the AAS Jan 11, 2007 Dying star's dust helping to build new planets Jan 11, 2007 Dr. Frankenstein stars electrify partners Jan 10, 2007 A star's death comes to light Jan 10, 2007 Death of a star: Supernova oddity prompts cosmic rethink Jan 7, 2007 Diamond star thrills astronomers Jan 6, 2007 Exploring Supernovae Jan 4, 2007 New Type Of Massive Stellar Death Dec 25, 2006 White Dwarf Hints at Our Solar System's End Dec 24, 2006 Dying Star May Presage Our Solar System's Demise Dec 23, 2006 A star of wonder could flash anytime now Dec 23, 2006 Dead star offers clues to the end of our Dec 22, 2006 Five billion years on ... disaster awaits Dec 22, 2006 Solar System's Fate Predicted by Nearby White Dwarf? Dec 22, 2006 Asymmetric Ashes: Astronomers Study Shape Of Stellar Candles Dec 5, 2006 Telescope captures double blast Nov 23, 2006 Dark energy nearly as old as the universe, scientists say Nov 17, 2006 Dark matter mystery grows Nov 17, 2006 'Dark Energy' Fueling Universe's Expansion Nov 17, 2006 First Directly Imaged Brown Dwarf Companion To An Exoplanet Host Star Oct 22, 2006 The Hecker Law Group PLC Announces Rock Star: Supernova Trademark Case Dismissed Sep 29, 2006 The Weirdest Type Ia Supernova Yet Sep 26, 2006 > read more Sep 23, 2006 Supernova size revises theory Sep 22, 2006 Exploding star 'breaks the rules' Sep 22, 2006 New supernova discovery breaks all the rules Sep 21, 2006 A 'Genetic Study' Of The Galaxy Sep 21, 2006 'Champagne supernova' challenges understanding of how supernovae ... Sep 21, 2006 Super supernova breaks the rules Sep 21, 2006 New supernova discovery defies theory Sep 21, 2006 Scientists Snap First Images Of Brown Dwarf In Planetary System Sep 20, 2006 How to Blow Up a Star Sep 19, 2006 Dwarf Planet Formerly Known As Xena Officially Named 'Eris' Sep 16, 2006 Faintest Flickers of Star Cluster Found Aug 19, 2006 Worth its SALT| Aug 19, 2006 Dead Star Exploding Aug 7, 2006 Red giant swallows brown dwarf, but doesn't digest it Aug 4, 2006 Red Giant fails to devour Brown Dwarf companion Aug 4, 2006 Dwarf survives in stellar furnace Aug 4, 2006 Stellar Survivor: Brown Dwarf Outlasts Red Giant Aug 3, 2006 Wannabe star escapes near-death experience Aug 3, 2006 Explosive-star mystery solved Jul 24, 2006 Astronomers glimpse exploded star Jul 23, 2006 Nuclear Explosion On A Dead Star Jul 21, 2006 Gemini yields supernova detail Jun 10, 2006 Galaxy Clusters Have Different Supernova Yields May 25, 2006 Companion Star Changed Supernova's Appearance May 16, 2006 Space Telescope's X-Ray Vision Reveals The Origin Of Elements In Galaxy Clusters May 12, 2006 Star Explodes Inside Another Star May 3, 2006
The arrow points to the supernova 2002bo, the explosion of a white dwarf in the galaxy NGC 3190 in the Leo constellation - 60 million light years away from Earth ... They have come to the conclusion that the explosion energy of the type Ia supernovae is almost consistent - it is equivalent to the fusion energy which a white dwarf with around one and half times the mass of the Sun can develop. (Science Daily)
Comet Chaos in the Helix's Heart Feb 22, 2007
C white dwarf that blew off its outer layers to form the nebula ... In addition, some of the stirred-up debris would eventually fall onto the white dwarf itself and this would explain its excess X-ray emission, a mystery up to now. (SkyAndTelescope.com)
The burned-out star, called a white dwarf, is the white dot in the center. Our sun will eventually burn out and shroud itself with stellar debris, but not for another 5 billion years. (Boston Globe)
Our star's outer layers will then fly off, and its core will shrink into a dense, fading object called a white dwarf ... Dust (central red cloud) surrounds a white dwarf in the famous Helix nebula ... Inside lies a white dwarf that is still hot. (Science News for Kids)
Then it will collapse, reaching the final stage of its existence: as an object called a white dwarf, like the tiny dot at the heart of the image above. It will collapse into a very dense object, cool down and die,' said Christensen. (Guardian Unlimited)
The nebula, which lies about 700 light-years from Earth, is the colorful remnant of a dying sunlike star that cast off its outer layers to become a white dwarf ... But as the dying star expanded, it blew these comets into each other's paths, so that they now jostle around and send dust swirling around the white dwarf. (National Geographic)
The University s Center for Astrophysical Thermonuclear Flashes will soon begin performing the world s most advanced simulations of exploding white dwarf stars with an allocation of 2 ... During the first tenths of a second after a slightly off-center ignition in a stellar white dwarf, a hot bubble of nuclear ash grows slowly as the nuclear flame burns slowly through the center of the star ... The Flash Center specializes in simulations of white dwarf stars. (Univeristy of Chicago Chronicle, IL)
On Tuesday NASA released this new shot of a dying star a white dwarf shown as a bright dot near the center of nebula NGC 2440 that was once similar to our sun. Low- to medium-size stars like our sun usually end their lives as white dwarfs ... The hot core left behind is a white dwarf. (National Geographic)
A favoured explanation is that the dust is being freshly churned up by comets smashing into each other in the outer fringes of the white dwarf's system. The dead white dwarf star lies at the centre of the Helix nebula ... Eventually, our own Sun will turn into a white dwarf. (Yahoo News -- Astronomy and Space)
The chaotic destruction of a dying white dwarf is a graphic glimpse of our Sun's future, according to NASA. ... NASA says the burned-out star, called a white dwarf, is casting off the outer layers of gas that had formed a cocoon around the star's remaining core ... The planetary nebula NGC 2440, a dying white dwarf, shoots a colourful 'last hurrah' to the universe. (Globe and Mail)
A very compact white dwarf withdraws matter from its unfortunate companion star. The matter forms a layer on the surface of the white dwarf ... "Because we measure the remains of 100 thousand million supernovae at once, we find more accurate averages than before. This will help the supernova community to learn how white dwarfs die.". (Science Daily)
Earth, robbed of its companion, would undertake a lonely vigil as the Sun turns eventually into a stellar corpse called a white dwarf Sun, fading to black over the ensuing trillions of years. Alternatively, if the swelling Sun loses 20 percent of its mass prior to it reaching our vicinity, both Earth and Moon could be spared incineration and remain together facing each other for eternity. (Yahoo News -- Astronomy and Space)
" It all comes down to numbers. Harnik argues that there will be countless more universes with myriad properties different from our own. By varying just one property, cosmologists have been too conservative. Harnik, Kribs and Perez decided to highlight this flaw in anthropic reasoning by taking a radical measure: They switched off the weak nuclear force, one of the four fundamental forces in nature. In practice, this means changing a multitude of parameters and constants simultaneously. The weak... (San Francisco Chronicle -- Opinion)
One star is a relatively normal star; the other is a collapsed star, such as a white dwarf, neutron star or even a black hole. If the stars are close enough together, the strong gravity of the collapsed star can pull off gaseous material from the normal star. (Science Daily)
This is the classic signature of a Type Ia supernova the thermonuclear detonation of a white dwarf that approaches the famous Chandrasekhar limit of 1 ... But Reynolds points out that the system as a whole might have been more massive than most Type Ia supernovae, and that perhaps the white dwarfs companion star shed considerable amount of gas in a stellar wind just as the white dwarf exploded. (SkyAndTelescope.com)
The key part of this result is what will happen when Mira A finishes its death throes and becomes a white dwarf in about one million years. The disk-creating process will have finished and the disk itself will be capable of forming new planets. (Science Daily)
Type Ia supernovae are the thermonuclear explosions of white dwarf stars, triggered when the star siphons off enough mass from a companion star to reach a critical mass of about 1. 4 times the mass of the Sun. (US Santa Cruz Currents, CA)
The system, EF Eridani, consists of a white dwarf and a brown dwarf in an orbit so tight it would fit inside the Sun. The system is normally active when material from the brown dwarf flows along magnetic field lines, smashing into the white dwarfs magnetic pole ... The magnetic field of the white dwarf penetrates the brown dwarf and acts like a conductor, says Kafka. (SkyAndTelescope.com)
"This discovery opens up a new way to search for young planets, by searching in double star systems that contain white dwarfs," Ireland said ... "It would pose a problem for life forms during the planetary formation process, while the white dwarf is still very young. But the white dwarf cools very quickly," Ireland said ... When Mira A contracts into a white dwarf, it will be about the size of the Earth, separated from Mira B by a distance equal to that between Earth and Pluto, and it will shine... (MSNBC -- Technology)
Shown here is a white dwarf star (left), whose strong magnetic field spurs activity in its low-mass partner ... White dwarf stars locked in binary systems can spawn solar flares, spots and other activity in their otherwise calm stellar neighbors, astronomers said this week ... Like Dr. Frankenstein zapping an inert corpse, the white dwarfs in these systems produce very strong electrical currents inside the bodies of their partner star, which can create violent eruptions where there otherwise... (MSNBC -- Technology)
These events occur when a white dwarf star pulls material from an orbiting companion until the white dwarf becomes unstable and is destroyed by a thermonuclear explosion. On the other hand, when viewed in optical light, the supernova remnant appears to be expanding into dense material that is rich in nitrogen. (EurekAlert!)
One is a so-called white dwarf -- the tiny, extremely hot, very dense core of an old star -- and the other is a "red giant," a cooling, ageing star that is running out fuel. The theory is that mass flows from the red giant to the white dwarf, which eventually collapses in on itself and explodes in a massive thermonuclear blast ... The astronomers suggest that a new class of supernovae may exist -- a supernova that evolves in the style of the Type 1a, but lives and dies much more swiftly, driven... (Yahoo News -- Astronomy and Space)
The huge cosmic diamond - technically known as BPM 37093 - is actually a crystallised white dwarf. A white dwarf is the hot core of a star, left over after the star uses up its nuclear fuel and dies ... For more than four decades, astronomers have thought that the interiors of white dwarfs crystallised, but obtaining direct evidence became possible only recently. (BBC News)
Type Ia supernovae occur when a medium mass star reaches the end stage of its life and becomes a white dwarf. If the white dwarf is part of a binary system, the white dwarf may begin pulling in material from the companion star, accreting material until it is pushed over the Chandrasekhar limit of about 1 ... The better choice for northern observers is RS Ophiuchi, a white dwarf that lies in Ophiuchus and is accumulating matter from its partner. (Suite101.com)
When stars that are smaller than our sun or up to 8 times more massive than the sun die, they expel the outer layers and leave behind a white dwarf in the centre. Stars with a mass more than 8 times that of our sun die violently in energetic supernova explosions expelling several solar masses of chemically enriched material into the interstellar medium leaving behind either neutron stars or black holes in the centre. (Science Daily)
While analyzing the light spectra of several hundred white dwarfs, astronomer Boris Gnsicke of the University of Warwick discovered evidence of a cool dust cloud around the white dwarf G29-38 ... G29-38 "had very, very unusual calcium emission lines in the red end of the spectrum, which white dwarfs shouldn't have, or which most shouldn't have anyway," Gnsicke told SPACE.com ... The chemical signature of light from the white dwarf suggested it was girdled by some kind of rotating gas disk, he... (Yahoo News -- Astronomy and Space)
New evidence suggests that white dwarf stars have planets orbiting them ... METALLIC RING: An unusual disk of gaseous, metallic debris around a white dwarf star 463 light years away provides a model for what could become of our solar system ... The star in question is a white dwarf known as SDSS1228+1040. (Scientific American)
STScI/ ESO / Tel Aviv U. / NASAImages such as this one from the Hubble Space Telescope show that the white dwarf T Pyxidis is not disrupted by its violent eruptions and accumulates more matter from its companion,repeating the cataclysm some years later ... T Pyxidis is composed of a dense white dwarf and a close companion star ... An outburst occurs when the temperature and density of the surge of matter dumped from the companion onto the surface of the white dwarf reach the nuclear flash... (MSNBC -- Technology)
Chicago, Dec 22: British astrophysicists have said that they have found evidence of planetary material in the orbit of a white dwarf for the first time, a discovery that may provide clues to the end of our own Solar System billions of years from now. The team at Britain's Warwick University identified an unusual ring of metal-rich gas orbiting very close around a white dwarf, a former star, about 463 light years from our Solar System in the constellation Virgo ... Their analysis of the traces of... (Zee News)
Astronomers foresee end of our solar system White dwarf contains an apocalyptic warning ... The white dwarf is now a hundred times smaller than our Sun, burning with a surface temperature 22,000C. ... Eventually the red giant will contract into the smaller, more dense, white dwarf. (Guardian Unlimited)
Solar System's Fate Predicted by Nearby White Dwarf ... Solar System's Fate Predicted by Nearby White Dwarf ... An unusual ring of metal-rich gas orbiting a white dwarf the remains of a burned-out star of modest mass has been spied within the constellation Virgo. (National Geographic)
"Using observations of 17 supernovae made over more than 10 years with ESO's Very Large Telescope and the McDonald Observatory's Otto Struve Telescope, astronomers inferred the shape and structure of the debris cloud thrown out from Type Ia supernovae. Such supernovae are thought to be the result of the explosion of a small and dense star - a white dwarf - inside a binary system. As its companion continuously spills matter onto the white dwarf, the white dwarf reaches a critical mass, leading to... (Science Daily)
Both were of the Type 1a variety, thought to form when a white dwarf - the remains of a low or medium mass star - pulls enough matter from a nearby companion star to produce a catastrophic explosion. Their uniform brightness is used to measure distances in the Universe. (BBC News -- Science)
The illumination from the explosions of white dwarf stars serve as distance markers for astronomers as they measure the cosmic growth rate. In 1998, Riess led another team of astronomers in one of the first studies that revealed the presence of dark energy. (Houston Chronicle)
He and several colleagues used the Hubble to observe 23 supernovae exploding white dwarf stars so distant their light took more than one-half the history of the universe to reach the orbiting telescope. That means the supernovae existed when the universe was less than one-half its current age of approximately 13. (Globe and Mail)
Dark Energy' Fueling Universe's Expansion (Tampa Bay Online, FL -- News)
In two cases, however, the astronomers found the companions to be white dwarfs, that is, stars at the end of their life ... One is a rather hot white dwarf, weighing. (Science Daily)
"The preliminary injunction that was sought from the Federal Court was really more of a white dwarf than a supernova in my view," said Gary Hecker of The Hecker Law Group, litigation counsel for Mark Burnett Productions. "The 90's punk band didn't ask the Court to stop the use of the word supernova. They only asked that the name Supernova be used in a way that would distinguish it from the 90's punk band pending trial. So we reached a settlement, which the Court encouraged." The parties reached... (Yahoo! Wire -- Entertainment News)
"Type Ia supernovae are thought to be reliable distance indicators because they have a standard amount of fuel the carbon and oxygen in a white dwarf star and they have a uniform trigger," says Nugent. "They are predicted to explode when the mass of the white dwarf nears the Chandrasekhar mass, which is about 1.4 times the mass of our sun. The fact that SNLS-03D3bb is well over that mass kind of opens up a Pandora's box." ... The white dwarf progenitors of Type Ia supernovae, typically about... (Science Daily)
D. Andrew Howell / Supernova Legacy Survey For decades, one of the canonical doctrines in astronomy is that a white dwarf cannot exceed 1 ... Until now, no white dwarf has even been observed above the Chandrasekhar limit, and the energies of Type Ia explosions were all consistent with a white dwarf at the limit ... First, the white dwarf might have contained around two solar masses, but was spinning so fast the centrifugal forces supported it against collapse. (SkyAndTelescope.com)
It originated from a "white dwarf," a dense evolved star with a mass far larger than any previously seen, reported University of Toronto postdoctoral researcher Andy Howell, lead author of the study ... The star reached about two solar masses before exploding, breaking a limit based on physical laws that a supernova explosion occurs when a white dwarf approaches 1 ... The "Champagne Supernova" team, speculating on reasons why the white dwarf became so huge before exploding, said possibly the... (Honolulu Star-Bulletin)
They are thought to form when a white dwarf - the remains of a low or medium mass star - pulls enough matter from a nearby companion star to explode in a violent thermonuclear reaction. According to the Indian physicist Subrahmanyan Chandrasekhar, no white dwarf can be more massive than about 1 ... "Type 1a supernovae are thought to be reliable distance indicators because they have a standard amount of fuel - the carbon and oxygen in a white dwarf star - and they have a uniform trigger," said... (BBC News -- Science)
Scientists in the past believed that dying stars, known as white dwarfs, could not expand to more than 1 ... The explosion also could have come from two white dwarf stars merging ... White dwarfs typically explode into supernovas after pulling gases from a nearby star. (ABC News Online, Australia)
They are currently interpreted as the disruption of small, compact stars, called white dwarfs, that acquire matter from a companion star. A white dwarf represents the penultimate stage of a solar-type star ... However, at some point the mounting weight of the accumulating material will have increased the pressure inside the white dwarf so much that the nuclear ashes in there will ignite and start burning into even heavier elements. (Science Daily)
University of Toronto postdoctoral researcher Andy Howell, lead author of the study, identified a Type Ia supernova named SNLS-03D3bb in a distant galaxy 4 billion light years away that originated from a dense evolved star, termed a 'white dwarf,' whose mass is far larger than any previous example. Type Ia supernovae are thermonuclear explosions that destroy carbon-oxygen white dwarf stars that have accreted matter from a companion star ... Current understanding is that Type Ia supernova... (News@UofT)
These explosions happen when a collapsed stellar remnant called a white dwarf sucks up material from a companion star until it reaches a critical mass, exactly 1 ... It is possible that the material falling into the white dwarf had a lot of momentum and accelerated the white dwarf's spin. (Nature News Service)
When the white dwarf's mass reaches 1 ... This along with the low kinetic energy of the star the energy of the flying objects from the explosion implies that the supernova originated from a white dwarf more massive than the Chandrasekhar limit. (MSNBC)
One is a rather hot white dwarf, weighing. . (Science Daily)
TEN SECONDS AFTER IGNITION, a thermonuclear flame has almost completed its incineration of a white dwarf star in this recent simulation ... Blowing Up Is Hard to Do Ironically, the stars that are thought to blow up as type Ia supernovae are usually paragons of stability--namely, white dwarf stars ... A white dwarf is the inert remnant of what used to be a sunlike star. (Scientific American)
ScienceDaily: Dwarf Planet Formerly Known As Xena Officially Named 'Eris. Dwarf Planet Formerly Known As Xena Officially Named 'Eris. (Science Daily)
The other group is made up of white dwarfs, which are the burnt relics of stars nearing the end of their lives ... These changes cause white dwarfs to take on a bluish, rather than reddish hue as they age ... Thanks to their old age, astronomers use white dwarfs as "clocks" to measure the universe s age. (Discovery Channel)
O'Donoghue said the observations of a "polar" binary star system containing a compact star called a white dwarf star, which has used its original store of nuclear energy before shrinking, and a relatively ordinary companion were the best of its kind made so far ... The results clearly showed the gravitational magnetic field of the white dwarf star pulling in gas from its companion, a phenomenon seen across the universe, from black holes at the centres of galaxies to pulsars and planets in... (iAfrica.com)
An artist shows what a blast wave from a huge nuclear explosion on the surface of a white dwarf in a two-star system 5,000 light-years from Earth might have looked like. Gas traveled from a red giant to the surface of a white dwarf, where it built up, then exploded ... One star is a white dwarf, which on its own would have finished burning. (Science News for Kids)
Troubled times are behind the brown dwarf for now, but its white dwarf companion will consume it in the end (Artist's impression: NASA) ... When stars like the Sun run out of hydrogen fuel in their cores, they bloat up into colossal red giants before shedding their outer layers entirely and becoming white dwarfs ... Astronomers led by Pierre Maxted at Keele University in Staffordshire, UK, studied a pair of stars labelled WD 0137-349, in which the more massive star is a white dwarf with 40%... (New Scientist Space)
One is a white dwarf - a star roughly earth-sized, but around half as massive as our sun, and the other is a brown dwarf - a failed star approximately 55 times as massive as Jupiter ... Millions of years ago, the white dwarf was a star very much like our own sun, and was orbited by its then much more distant brown dwarf companion ... And so the star shed its outer layers in a planetary nebula (nothing to do with planets), leaving its core intact, and visible to us as a white dwarf. (Register)
The two objects will be so close that the white dwarf will work as a giant 'vacuum cleaner', drawing gas off its companion, in a cosmic cannibal act ... The dying core eventually turns into a white dwarf - a spherical body the size of the Earth, made up of carbon and oxygen ... "We've discovered a small failed star called a brown dwarf lying next to another star called a white dwarf and the two are orbiting each other in a tiny orbit of two hours," Dr Matt Burleigh, a co-author of the paper and... (BBC News -- Science)
This leaves behind a small, so-called white dwarf consisting of the residual helium core. Now scientists have discovered an unusual binary star system consisting of a brown dwarf (a pseudostar 55 times the size of Jupiter but still too small to reliably fuse hydrogen) and a white dwarf ... The brown dwarf may have even gained mass from the common envelope that existed during the system's (known as WD 0137-349) red giant phase (depicted in the image at right with the red center showing the future... (Scientific American)
At the end of this period the red giant left behind only a lifeless core, known as a white dwarf, around which the surviving brown dwarf was left in orbit. ADVERTISEMENT. (Nature News Service)
The star is a stellar corpse the size of Earth, known as a white dwarf, and it is paired in a binary system with a red giant, a dying, bloated star that once resembled our sun. The red giant has been dumping gas onto the surface of the white dwarf, and every few years, enough matter accumulates to set off a giant thermonuclear explosion ... The latest observations instead showed that the explosion evolved into two lobes, confirming suspicions that the nova outburst produces twin jets of stellar... (SportsIllustrated.CNN -- Racing)
It has long been believed that type 1a supernovae are the death throes of a white dwarf star ... RS Ophiuci, in the equatorial constellation of Ophiuchus (near Libra), is just the right kind of white dwarf ... "It started slowing down almost immediately, within just two days, and that tells us the white dwarf must be extremely massive, in fact almost massive enough to collapse.". (BBC News -- Science)
Gas captured from one star, a red giant, builds up on the surface of its white dwarf companion (a super-dense dead star about the size of the Earth which was once the core of a star like the Sun whose outer layers have been lost into space). Eventually enough gas collects on the white dwarf for thermonuclear reactions to begin, similar to those which power the Sun but which runaway into a massive explosion ... "A week after our first observations, we combined telescopes across Europe with two in... (Science Daily)
Astronomers have long known that a white dwarf star sucking in matter from a bigger companion can blow itself apart, scattering atoms which later clump together into dust. But such a Type I supernova takes a long time to develop, said Roy. (Honolulu Star-Bulletin)
ESA's XMM-Newton observatory recently watched two galaxy clusters enabling astronomers to learn that these clusters have higher quantities of Type 1a supernovae - exploding white dwarf stars - than our own galaxy ... The Type Ia supernovae explode when a white dwarf star consuming matter from a companion star becomes too massive and completely disintegrates ... "Comparing the abundances of the detected elements to the yields of supernovae calculated theoretically, we found that about 30 percent... (Universe Today)
But then the tell tale hydrogen surrounding it disappeared, and astronomers had to re-classify it as a Type I supernova - when a white dwarf steals matter from a companion. Astronomers using the Gemini telescope in Chile think they've solved the mystery. (Universe Today)
The Type Ia supernovae explode when a white dwarf star consuming matter from a companion star becomes too massive and completely disintegrates ... "Comparing the abundances of the detected elements to the yields of supernovae calculated theoretically, we found that about 30 percent of the supernovae in these clusters were exploding white dwarfs ( Type Ia ) and the rest were collapsing stars at the end of their lives ( core collapse )," said Norbert Werner, from the SRON Netherlands Institute for... (Science Daily)
This white dwarf star has brightened like this 5 times in the last 100 years, and astronomers believe it's about to collapse into a neutron star ... The two stars are so close that the white dwarf is actually inside the envelope of the red giant, and explodes from within it every 20 years or so ... It consists of a white dwarf star (the super-dense core of a star, about the size of the Earth, that has reached the end of its main hydrogen-burning phase of evolution and shed its outer layers) in... (Universe Today)
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