White Dwarfs


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Related to White Dwarfs: Neutron stars

White Dwarfs

 

(astronomy), very dense small hot stars consisting of degenerate gas. The mass of an ordinary white dwarf averages about 1, the radius about 0.2, and the luminosity about 0.01 of the corresponding values of the sun. The average density of a white dwarf ranges from 104 to 106 g/cm3. The first white dwarf, a satellite of Sirius (a white star 10,000 times fainter than Sirius), was discovered from the distorted movements of the main star caused by attraction of the satellite. The discovery of dwarf stars confirmed the physical theory which holds that the size of bodies of degenerate gas is inversely proportional to their mass. Dwarf stars are considered the final stage in the evolution of ordinary stars after exhaustion of the thermonuclear sources of energy. They may also be related to pulsars.

A. G. MASEVICH

References in periodicals archive ?
For decades it has been theoretically clear that that young white dwarfs are contracting," researcher Sergei Popov said in the statement.
Using the deflection measurement, the Hubble astronomers calculated that the white dwarfs mass is roughly 68 percent of the suns mass.
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British astronomers scouring data from a major star-mapping study have now identified two white dwarfs with large amounts of oxygen in their atmospheres.
At the end of its life, the sun will become a white dwarf.
The 127 contributions are organized into eight sections: white dwarf structure and evolution; white dwarf mass distribution and luminosity function; white dwarfs in stellar clusters and the galactic halo; white dwarfs in large surveys; atmospheres, abundances and magnetic fields; white dwarf dust disks and planetary systems; white dwarfs in binaries; and variable white dwarfs.
British astronomers from the universities of Leicester and Cambridge hope to get round the "dazzle" problem by concentrating on white dwarfs.
After the ``degenerate era,'' even the white dwarfs and neutron stars will be gone, they say.