Latest White dwarf Stories
ESAâ€™s X-ray observatory XMM-Newton has revealed a new class of exploding stars â€“ where the X-ray emission â€˜lives fast and dies youngâ€™.
Hubble has obtained the first direct optical images of the aftermath of a recent titanic explosion that took place in a star system 5,000 light years from Earth.
Astronomers have found the lowest mass white dwarf known in our galaxy: a Saturn-sized ball of helium containing only about one-fifth the mass of the Sun.
It has been a mystery for astronomers how certain dying stars have their colossal quantities of material blown out into the universe and shrink into objects called "white dwarves".
Proof that certain double star systems can erupt in full-blown explosions and then continue to flare up with smaller bursts has been spotted by the ultraviolet eyes of NASA's Galaxy Evolution Explorer.
A bunch of rowdy comets are colliding and kicking up dust around a dead star, according to new observations from NASA's Spitzer Space Telescope. The dead star lies at the center of the much-photographed Helix nebula.
The universe contains one and a half times more calcium than previously assumed. This conclusion was drawn by astronomers of the SRON Netherlands Institute for Space Research, after observations with ESA's XMM-Newton X-ray observatory.
Scientists have created a stunning new image of one of the youngest supernova remnants in the galaxy. This new view of the debris of an exploded star helps astronomers solve a long-standing mystery.
Evidence for a significant new class of supernova has been found with NASA's Chandra X-ray Observatory. These results strengthen the case for a population of stars that evolve rapidly and are destroyed by thermonuclear explosions.
Using observations of 17 supernovae made over more than 10 years with ESO's Very Large Telescope and the McDonald Observatory's Otto Struve Telescope, astronomers inferred the shape and structure of the debris cloud thrown out from Type Ia supernovae.
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...
- totally perplexed and mixed up.