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Latest White dwarf Stories

Aging Stars Sculpt Spectacular Shape Of Planetary Nebula
2012-11-08 14:21:55

[ Video 1 ] | [ Video 2 ] | Video 3 ] Lee Rannals for redOrbit.com - Your Universe Online Astronomers have discovered a pair of stars orbiting each other at the center of a remarkable example of a planetary nebula. The latest find confirms a theory about what controls the spectacular and symmetric appearance of the material flung out into space. Planetary nebulae are glowing shells of gas around white dwarfs, and Fleming 1 is considered a great example that has strikingly...

New Scenario for the Birth of Type Ia Supernovae
2012-10-26 05:49:37

Lee Rannals for redOrbit.com - Your Universe Online Astronomer J. Craig Wheeler reports in The Astrophysical Journal that he has a new theory on the identity of the "parents" of Type Ia supernovae. Wheeler said that current theories of Type Ia parents do not correctly match up with telescope data on actual supernovae. There are two models today that attempt to explain how Type Ia supernovae are born, the first being "single-degenerate model." In this model, a binary star is made...

Old Star May Have A Companion
2012-10-10 15:10:33

[ Watch the Video: Slicing Through View of the Material Around R Sculptoris ] Lee Rannals for redOrbit.com - Your Universe Online Astronomers have discovered an unexpected spiral structure in the material around an old star called R Sculptoris The team used the Atacama Large Millimeter/submillimeter Array (ALMA) to discover the surprising spiral structure in the gas around the red giant star, which could mean there is a previously unseen companion star orbiting the star....

Supernova Was Caused By A Yellow Supergiant
2012-09-29 06:47:07

redOrbit Staff & Wire Reports - Your Universe Online A team of Japanese researchers has discovered evidence that a yellow supergiant (YSG) was, in fact, the progenitor for a recently discovered supernova -- a discovery which they say raises serious questions regarding our understanding of the evolution of massive stars. Melina Bersten of the Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) and colleagues analyzed evidence and discovered that supernova...

Supernova Cause Revealed A Millennium Later
2012-09-28 10:32:37

April Flowers for redOrbit.com - Your Universe Online Just over 1,000 years ago, one of the brightest stellar events ever recorded in history occurred. Between April 30 and May 1, 1006, a supernova was widely observed by a number of civilizations across the globe. Now, more than a thousand years later, a research team led by the University of Barcelona, the Instituto de Astrofisica de Canarias (IAC) and the Instituto de Ciencia de Materiales de Madrid (CSIC) has determined that SN 1006 was...

Searching For Supernova Progenitors
2012-08-04 06:23:15

Lee Rannals for redOrbit.com - Your Universe Online A progenitor of a type 1a supernova may have been found, according to findings published in the journal Monthly Notices of the Royal Astronomical Society. Astronomers believe that type 1a supernovae are thermonuclear explosions of a white dwarf star that is part of a binary system, which is two stars that are physically close and orbit a common center of mass. The white dwarf has mass gradually given to it by its companion star, and...

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...


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
mallemaroking
  • Nautical, the visiting and carousing of sailors in the Greenland ships.
This word is apparently from a confusion of two similar Dutch words: 'mallemerok,' a foolish woman, and 'mallemok,' a name for some persons among the crew of a whaling vessel.