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Latest White dwarf Stories

Wide-field view of the Andromeda Galaxy
2012-06-02 08:41:25

Unfortunately, stars don't have birth certificates. So, astronomers have a tough time figuring out their ages. Knowing a star's age is critical for understanding how our Milky Way galaxy built itself up over billions of years from smaller galaxies. Jason Kalirai of the Space Telescope Science Institute and The Johns Hopkins University's Center for Astrophysical Sciences, both in Baltimore, Md., has found the next best thing to a star's birth certificate. Using a new technique, Kalirai...

Two Different Sources for Supernova, Both Models Are Correct
2012-05-07 10:40:40

The exploding stars known as Type Ia supernovae serve an important role in measuring the universe, and were used to discover the existence of dark energy. They're bright enough to see across large distances, and similar enough to act as a "standard candle" - an object of known luminosity. The 2011 Nobel Prize in Physics was awarded for the discovery of the accelerating universe using Type Ia supernovae. However, an embarrassing fact is that astronomers still don't know what star systems make...

Image 1 - Exoplanet-Consuming White Dwarf Stars Discovered
2012-05-03 10:19:16

Astrophysicists at a UK university have found a quartet of white dwarf stars which they say are in the process of consuming exoplanets that were once similar in composition to Earth. According to a Thursday press release, researchers from the University of Warwick said that the four stars which they observed were surrounded by dust from shattered planetary bodies. They used the Hubble Space Telescope to survey the chemical composition of those stars' atmospheres, and discovered that the...

2012-04-13 03:26:20

A University of Oklahoma assistant professor and colleagues have identified two white dwarf stars considered the oldest and closest known to man.  Astronomers identified these 11- to 12-billion-year-old white dwarf stars only 100 light years away from Earth.  These stars are the closest known examples of the oldest stars in the Universe forming soon after the Big Bang, according to the OU researcher. Mukremin Kilic, assistant professor of physics and astronomy in the OU College...

Image 1 - Astrophysicists Gain Insight Into Star Creation From NASA Satellite
2012-03-21 07:47:08

NASA's Swift satellite puts faraway stars and galaxies under a new lens. A combination of X-ray and ultraviolet observations from NASA's Swift satellite allow researchers to gain a more detailed look at specific stars and their activities. Most recently Swift was used to study a Type Ia supernova. While it's been known that Type Ia supernovae originate with a remnant star called a white dwarf, the X-ray and ultraviolet views allow researchers to view the events and matter that cause the...

Image 1 - Important Clue Uncovered For Origins Of A Type Of Supernovae Explosion
2012-03-04 06:11:31

Pitt team used Sloan Digital Sky Survey to determine that the merger of double white dwarfs is a plausible explanation for Type Ia supernovae The origin of an important type of exploding stars–Type Ia supernovae–have been discovered, thanks to a research team at the University of Pittsburgh. Studying supernovae of this type helps researchers measure galaxy distances and can lead to important astronomical discoveries. A paper detailing this research has been accepted for...

Astronomers Solve 40-year Mystery Of Nearby Supernova
2012-01-12 05:57:49

NASA's Hubble Space Telescope has helped astronomers solve a 40-year mystery over what type of star, or so-called progenitor, caused a supernova in a nearby galaxy. The powerful telescope´s findings have provided new observational data for identifying one of several scenarios that trigger such outbursts. Based on previous observations from ground-based telescopes, astronomers knew the supernova class, called a Type Ia, created a remnant named SNR 0509-67.5, which lies 170,000...

August Supernova Was A White Dwarf
2012-01-11 13:25:22

Fluke observation 4 hours after star exploded allows stronger limits on size of progenitor Last year's discovery of the nearest Type Ia supernova in decades — captured only 11 hours after it exploded — allowed astronomers to finally cinch the identity of the stars behind these explosions, which have become key measures of cosmic distance. That supernova, called SN2011fe, and presumably most Type Ia supernovae were originally white dwarfs extremely dense and compact stars...


Latest White dwarf Reference Libraries

6_c21be0ecb1b565a9be109a383c38223f2
2004-10-19 04:45:43

White Dwarf -- A white dwarf is a a star supported by electron degeneracy. A star like our Sun will become a white dwarf when it has exhausted its nuclear fuel. Near the end of its nuclear burning stage, such a star goes through a red giant phase and then expels most of its outer material (creating a planetary nebula) until only the hot (T > 100,000 K) core remains, which then settles down to become a young white dwarf. A typical white dwarf is half as massive as the Sun, yet only...

6_dac4e7d6b8fb5cf3a1458d796b90d7a92
2004-10-19 04:45:42

Stellar Evolution -- Stellar evolution is the process of formation, life, and death of stars. It is one of the major topics of cosmogony. Star Birth and Life A star starts out as an enormous cloud of gas and dust many light-years across. Star formation begins when the cloud begins to condense under its own gravity. The processes that initiate this contraction are not fully understood. The cloud fragments fuse into stellar mass clouds known as protostars. Protostars do not emit...

6_19859ff34fd03d00777232e2520ce83f4
2004-10-19 04:45:42

Nova -- A nova is an enormous nuclear explosion caused by the accretion of hydrogen onto the surface of a white dwarf star. When a white dwarf has a close companion star, the companion will often begin to have its outer atmosphere drawn away from it by the white dwarf's gravity as the companion star ages and expands into a red giant. The gases so captured consist primarily of hydrogen and helium, the two principle constituents of matter in the universe. The gases are compacted on the...

6_f1577ee462b741c03ef6a7d23d2cd6904
2004-10-19 04:45:41

Cataclysmic Variable Star -- Cataclysmic variables are a class of binary stars containing a white dwarf and a companion star. The companion star is usually a red dwarf, although in some cases it is another white dwarf or a slightly evolved star (subgiant). Several hundreds of cataclysmic variables are known. From the observational viewpoint, cataclysmic variables are relatively easy to discover. They are usually quite blue objects, as the majority of stars are red. The variability of...

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Word of the Day
vermicular
  • Like a worm in form or movement; vermiform; tortuous or sinuous; also, writhing or wriggling.
  • Like the track or trace of a worm; appearing as if worm-eaten; vermiculate.
  • Marked with fine, close-set, wavy or tortuous lines of color; vermiculated.
  • A form of rusticated masonry which is so wrought as to appear thickly indented with worm-tracks.
This word ultimately comes from the Latin 'vermis,' worm.
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