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Latest White dwarf Stories

Ancient Brown Dwarfs
2013-11-21 15:05:41

John P. Millis, PhD for redOrbit.com - Your Universe Online The galaxy is a diverse place, containing stars, planets, nebulous gas, black holes, and all matter of other objects, some of which we still do not understand. But among this vast array sits an object that is neither a star, nor a planet. These brown dwarfs have masses only a fraction of that of our Sun, but are still at least 13 times more massive than Jupiter. But because of the lack of substantial fusion, the surface of...

NASA Scientists Discover Cool Brown Dwarfs That Are Still Pretty Warm
2013-09-06 11:02:56

Brett Smith for redOrbit.com - Your Universe Online Two years ago NASA scientists revealed a new class of stars, dubbed ‘Y dwarfs,' thought to be about as warm as the human body. However, newly published research indicates that these cold stars are probably a bit warmer than the boiling point of water. These stars are believed to have a mass about 5 to 20 times that of Jupiter. Unlike our sun, these types of brown dwarf stars derive their energy via gravitational contraction, a...

Nova Visible With Naked Eye
2013-08-20 10:36:11

John P. Millis, PhD for redOrbit.com - Your Universe Online White dwarfs – small balls of carbon and oxygen, the core remnants of Sun-like stars that reached the ends of their lives – give off a soft glow of light, slowly fading as the heat from their surfaces escapes into the coldness of space. These dead cores will eventually dim and cool, as nuclear fusion has long ceased. However, there are some that live on. These white dwarfs orbit in close binary systems with another star. If...

Nature's Constants Not Constant
2013-07-05 08:29:31

Lee Rannals for redOrbit.com - Your Universe Online An international team of astronomers wrote in the journal Physical Review Letters they were able to test a controversial theory about the constants of nature. The team studied a distant white dwarf star using the Hubble Space Telescope to measure the strength of the electromagnetic force, or alpha, one of the four fundamental forces that shape the universe as we know it. The researchers hoped to determine whether the laws of physics...

Stellar Collision Survivor New Type Pulsating Star
2013-06-28 14:54:18

Lee Rannals for redOrbit.com - Your Universe Online Astronomers have discovered that the brightness of the remnant of a stellar collision can vary in a way that scientists have not observed before. The team wrote in the journal Nature that these observations will allow astronomers to learn what happens when stars collide in binary systems. Stars like our Sun expand to become red giant stars when the hydrogen that fuels the nuclear fusion in their cores runs out. Binary stars will...

Chandra Discovers Supernova Remnant Emission Is Synchrotron Radiation
2013-06-26 16:32:40

Lee Rannals for redOrbit.com – Your Universe Online Astronomers will be reporting details about a supernova remnant known as G1.9+0.3 in the upcoming issue of The Astrophysical Journal Letters. In 2008, a team of scientists discovered the remains of a supernova known to have occurred in the Milky Way, about 28,000 light years away from Earth. The explosion would have been visible from Earth a little more than a hundred years ago, assuming it was not obscured by dust and gas....

Pulsating White Dwarf Discovered By UT Astronomers
2013-06-20 12:47:40

Lee Rannals for redOrbit.com - Your Universe Online A group of astronomers have discovered pulsations from the crystallized remnant of a burnt-out star. The researchers recently reported in The Astrophysical Journal Letters that they were able to use the 2.1-meter Otto Struve Telescope at the University of Texas McDonald Observatory to take a look at the white dwarf GD 518 and discover the pulsations. This finding will allow scientists to see below the star's atmosphere and into its...

Supernova Light Echo Detected
2013-06-05 13:28:46

Lee Rannals for redOrbit.com - Your Universe Online Astronomers discovered light echoing off of material surrounding a recent supernova explosion, supporting the theory that exploding white dwarfs become unstable from matter donated by large non-degenerate stars. The team detected the light echo coming off of SN 2009ig, making it the sixth and most luminous discovered from a type Ia supernova. A light echo works similarly in principle to the more familiar sound echoes heard on Earth....

Star Songs Plucked From The Cosmos
2013-06-01 05:44:51

redOrbit Staff & Wire Reports - Your Universe Online Researchers from the Harvard-Smithsonian Center for Astrophysics (CfA) have blended science, technology and art to create a unique new website that allows people to listen to original musical compositions crafted from cosmic x-rays. The Star Songs website was published by research associate Gerhard Sonnert, who worked with University of Glasgow postdoctoral student Wanda Diaz-Merced and composer Volkmar Studtrucker on the project....

White Dwarf Star Cooling Rates Updated By New Data
2013-05-29 16:00:35

Lee Rannals for redOrbit.com — Your Universe Online University of British Columbia (UBC) astronomers have determined that white dwarfs cool more slowly in the early stages of their life than models have previously predicted. White dwarfs are the dense, hot remnant cores of stars that have used up all of their fuel and lost their outer layers during the red giant phase. When these objects form, their surface temperatures are very hot, but cool over time as they radiate their...


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
glogg
  • Scandinavian punch made of claret and aquavit with spices and raisins and orange peel and sugar.
This word comes from the Swedish 'glogg,' which is an alteration of 'glodgat,' mulled (wine).
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