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Shrinking giants, exploding dwarves
August 28, 2007When white dwarf stars explode, they leave behind a rapidly expanding cloud of 'stardust' known as a Type Ia supernova. These exploding events, which shine billions of times brighter than our sun, are all presumed to be extremely similar, and thus have been used extensively as cosmological reference beacons to trace distance and the evolution of the Universe.
Astronomers have now - for the first time ever - provided a unique set of observations obtained with the ESO Very Large Telescope in Chile and the 10-meter Keck telescope in Hawaii, enabling them to find traces of the material that had surrounded a white dwarf star before it exploded. Their data set is unique in that no Type Ia supernova event has ever been observed at this level of detail over a several-month period following the explosion.
These observations support a widely accepted model proposing that a white dwarf star interacts with a companion star - a red giant. Due to the white dwarf's strong gravitational pull, this companion star continuously loses mass through 'force feeding' its gases to the white dwarf. When the mass of the white dwarf grows past a critical value, it explodes.
Through their observations, which took place over the course of four months, and combined with archival data, the astronomers detected the presence of a number of expanding shells surrounding a Type Ia super-nova event. The make-up of these shells suggests they are the remnants of the red giant star that fed the white dwarf.
These results were recently published in the journal Science. The data were collected by two teams of researchers; one at ESO headed by Dr. Ferdinando Patat, and one at the California Institute of Technology, USA, led by Dr. Avishay Gal-Yam. Dr. Gal-Yam has recently joined the Weizmann Institute of Science as a senior scientist in the Condensed Matter Physics Department.
Weizmann Institute of Science
Through their observations, which took place over the course of four months, and combined with archival data, the astronomers detected the presence of a number of expanding shells surrounding a Type Ia super-nova event. The make-up of these shells suggests they are the remnants of the red giant star that fed the white dwarf.
These results were recently published in the journal Science. The data were collected by two teams of researchers; one at ESO headed by Dr. Ferdinando Patat, and one at the California Institute of Technology, USA, led by Dr. Avishay Gal-Yam. Dr. Gal-Yam has recently joined the Weizmann Institute of Science as a senior scientist in the Condensed Matter Physics Department.
Weizmann Institute of Science
White Dwarf Current Events and White Dwarf News RSSGerman high-school students involved in an astronomical research project
This week, Astronomy & Astrophysics publishes a somewhat unusual research article because it is co-authored by German high-school students.
Berkeley Lab Scientists' Computer Code Gives Astrophysicists First Full Simulation of Star's Final Hours
The precise conditions inside a white dwarf star in the hours leading up to its explosive end as a Type Ia supernova are one of the mysteries confronting astrophysicists studying these massive stellar explosions.
XMM-Newton uncovers a celestial Rosetta stone
ESA's XMM-Newton orbiting X-ray telescope has uncovered a celestial Rosetta stone: the first close-up of a white dwarf star, circling a companion star, that could explode into a particular kind of supernova in a few million years.
Peculiar, junior-sized supernova discovered by New York teen
In November 2008, Caroline Moore, a 14-year-old student from upstate New York, discovered a supernova in a nearby galaxy, making her the youngest person ever to do so.
NC State Researchers
Researchers at North Carolina State University have used a mathematical model that allows them to get a clearer picture of the galaxy's youngest supernova remnant by correcting for the distortions caused by cosmic dust.
Largest collection of anomalous white dwarfs observed in new Hubble images
Twenty-four unusual stars, 18 of them newly discovered, have been observed in new Hubble telescope images. The stars are white dwarfs, a common type of dead star, but they are odd because they are made of helium rather than the usual carbon and oxygen. This is the first extensive sequence of helium-core white dwarfs to be observed in a globular cluster, a dense swarm of some of the oldest stars in our galaxy.
UBC researchers develop breakthrough technique to unlock the secret of plasmas
University of British Columbia researchers have developed a technique that brings scientists a big step closer to unlocking the secrets of the most abundant form of matter in the universe.
Action Replay of Powerful Stellar Explosion
Astronomers have made the best ever determination of the power of a supernova explosion that was visible from Earth long ago. By observing the remnant of a supernova and a light echo from the initial outburst, they have established the validity of a powerful new method for studying supernovas.
Supernova remnants dance in the LMC
The Gemini South Multi-Object Spectograph (GMOS) recently captured a dramatic image of a vast cloud complex named DEM L316 located in the Large Magellanic Cloud.
White Dwarf Pulses Like a Pulsar
New observations from Suzaku, a joint Japanese Aerospace Exploration Agency (JAXA) and NASA X-ray observatory, have challenged scientists' conventional understanding of white dwarfs. Observers had believed white dwarfs were inert stellar corpses that slowly cool and fade away, but the new data tell a completely different story.
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White Dwarf White Dwarf DVD Pal FORMAT (Region code all) Review Summary In this made-for-TV sci-fi-drama, the world has entered into an age when travel between the planets has become an everyday event, and Driscoll Rampant (b), a medical student, finds himself taking an internship on the distant planet of Rusta. Unlike Earth, Rusta does not turn on its axis as it orbits through space, with one half of the planet in constant daylight and the other in permanent nighttime; as a result, Rusta has two very different civilizations, one a genteel land of ladies and gentlemen, the other a feudal kingdom. As Rampant travels between the two sides of Rusta, he struggles to build a bridge between both sides in a world where the essential duality of man is brought clearly to the forefront. White Dwarf also stars... |
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White Dwarf #197 (US Edition, June 1996) by Games Workshop (Author) Square-bound magazine published by Games Workshop (makers of the popular Warhammer & Warhammer 40K tabletop miniatures games). This issue features designer's notes for the Wood Elf army book and rules for foreign travel in Warhammer Quest. As usual, this magazine is crammed full of hobby tips, painting tips, scenario ideas, variant rules and gorgeous pictures of painted Citadel Miniatures. |
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The Birth by Stardeath & White Dwarfs After traversing the galaxy as the road crew for fellow Oklahomans The Flaming Lips, a strange yet melodically intoxicating band has emerged-psych/prog/experimental pop quartet Stardeath And White Dwarfs. One half stoners with nothing to do but roll joints on their King Crimson record sleeves and one-half confetti launchers/ space bubble technicians, Stardeath And White Dwarfs debut their own free-floating circus with their first full-length album, The Birth. A mind-trip of emotion and mood, recalling everything from 'upper' dance freak-outs to 'downer' Floyd-esque anthems, The Birth celebrates a love of all things psychedelic. |
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Disney Princess Snow White and the Seven Dwarfs Gift Set by Mattel She's the fairest of them all! Snow White's got the world's first entourage! Add to your Disney Princess collection!Snow White doll sparkles in her fairytale gown and tiara, surrounded by all 7 charming dwarf characters - Bashful, Dopey, Sneezy, Grumpy, Sleepy, Doc and Happy. A classic gift set! Doll cannot stand alone. |
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White Dwarf [VHS] Starring: Paul Winfield, Neal McDonough, Ele Keats, Giuseppe Andrews, Tara Graham Directed By: Peter Markle |
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Snow White and the Seven Dwarfs Starring: Adriana Caselotti, Harry Stockwell, Lucille La Verne, Roy Atwell, Stuart Buchanan Directed By: David Hand No film in history has captured the worlds imagination like Walt Disneys first full-length animated masterpiece. Through astonishing Blu-ray high definition technology, experience this timeless classic in its most spectacular presentation ever! With an all-new, state-of-the-art digital restoration and Disney Enhanced High Definition sound, the breathtaking animation and unforgettable music of the most revered Disney film of all time will enthrall you like never before! Join the beautiful princess Snow White as she escapes her jealous stepmother, the queen, and befriends a lovable group of dwarfs. But when she falls under the queens wicked spell, only true loves kiss can save her. |
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The Birth Stardeath And White Dwarfs (Primary Contributor) |
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Jim Shore Disney Traditions Snow White's Seven Dwarfs 4005434 "Homeward Bound" by Enesco Heigh Ho, Heigh Ho its Homeward Bound they go. Doc, Grumpy, Happy, Bashful, Sleepy, Sneezy and Dopey are all here in this intricately sculpted figure from Disney Traditions designed by Jim Shore. Inspired by Walt Disney's Snow White and the Seven Dwarfs, this charming figurine brings back the spell of childhood memories that live in our hearts, inspire our hopes, and illuminate our dreams. |
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Sexy Adult Womens Costumes Snow White And The Seven Dwarfs Fancy Dress Costume Theme Party Outfit Leg Avenue Medium/Large, Yellow/Blue by Fenvy 2 Piece Classic Snow White Costume, includes headband and dress with bow back and glitter apple applique. |
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Snow White and the Seven Dwarfs (Two-Disc Blu-ray/DVD Combo + BD Live w/ Blu-ray packaging) [Blu-ray] Starring: Adriana Caselotti, Roy Atwell, Lucille LaVerne Directed By: David Hand No film in history has captured the worlds imagination like Walt Disneys first full-length animated masterpiece. Through astonishing Blu-ray high definition technology, experience this timeless classic in its most spectacular presentation ever! With an all-new, state-of-the-art digital restoration and Disney Enhanced High Definition sound, the breathtaking animation and unforgettable music of the most revered Disney film of all time will enthrall you like never before! Join the beautiful princess Snow White as she escapes her jealous stepmother, the queen, and befriends a lovable group of dwarfs. But when she falls under the queens wicked spell, only true loves kiss can save her Bonus Features Include: Snow White Returns Storyboard Featurette Was Walt planning a Snow White... |
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