Latest White dwarf Stories
Just over 1,000 years ago, one of the brightest stellar events ever recorded in history was widely observed by a number of civilizations across the globe.
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.
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.
Two very different models explain the possible origin of Type Ia supernovae, and different studies support each model. New evidence shows that both models are correct - some of these supernovae are created one way and some the other.
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.
A University of Oklahoma assistant professor and colleagues have identified two white dwarf stars considered the oldest and closest known to man.
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.
Pitt team used Sloan Digital Sky Survey to determine that the merger of double white dwarfs is a plausible explanation for Type Ia supernovae.
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.
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...
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...
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...
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...
Sirius -- Sirius (Î± Canis Major, also known as the Dog Star) is the brightest star (-1.46m) in the night sky and can be seen from every inhabited region of the Earth's surface. At a distance of 8.6 light years, Sirius is also one of the nearest stars to Earth. It is a main sequence star of spectral type A0 or A1 and has a mass about 2.4 times that of the Sun. Sirius has a white dwarf companion called Sirius B which orbits it with a period close to 50 years. It was the first white...
- A person who stands up for something, as contrasted to a bystander who remains inactive.
- One of the upright handlebars on a traditional Inuit sled.