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black dwarf

noun, Astronomy
See under white dwarf.

white dwarf

noun, Astronomy
a star, approximately the size of the earth, that has undergone gravitational collapse and is in the final stage of evolution for low-mass stars, beginning hot and white and ending cold and dark (black dwarf)
Origin of white dwarf
1920-25 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the Web for black dwarf
Historical Examples
  • This is "the black dwarf," or Sir Edward Mauley, the hero of the novel.

  • "It's a dead white dwarf—a 'black dwarf', you might say," Morey replied.

    Islands of Space John W Campbell
  • Modeste had christened this grotesque little being her "black dwarf."

    Modeste Mignon Honore de Balzac
  • What would the 'black dwarf' be if every one knew from the beginning that he was a rich man and a baronet?

    Dr. Wortle's School Anthony Trollope
  • His watchfulness availed him nothing, however, for no further sign of the black dwarf.

  • I will go first to show you the way, and where a black dwarf can pass, there you white people who are so much braver can follow.

    The People Of The Mist H. Rider Haggard
  • The black dwarf had been sent for from the castle, the outwardly stolid and incurious maid-of-all-work informed him.

    The White Blackbird Hudson Douglas
  • Then he lit his pipe at the blue light, and the black dwarf was before him in a moment.

    Children's Literature Charles Madison Curry
  • The "black dwarf" was not written till a good many years after Ritchie's death.

  • The black dwarf sun sent its assassin on a mission which was calculated to erase the threat to its existence.

    The Honored Prophet William E. Bentley
British Dictionary definitions for black dwarf

white dwarf

one of a large class of small faint stars of enormous density (on average 108 kg/m³) with diameters only about 1 per cent that of the sun, and masses less than the Chandrasekhar limit (about 1.4 solar masses). It is thought to mark the final stage in the evolution of a sun-like star
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for black dwarf

in astrophysics, a kind of dead and lightless star, 1966.

Online Etymology Dictionary, © 2010 Douglas Harper
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black dwarf in Science
black dwarf  
The theoretical celestial object that remains after a white dwarf has used up all of its fuel and cooled off completely to a solid mass of extremely dense, cold carbon. A white dwarf will eventually become a black dwarf unless it has a companion star from which it can take sufficient mass to pass the Chandrasekhar limit and collapse into a neutron star or black hole. No black dwarf has ever been observed. Because the estimated cooling time for a white dwarf is in the trillions of years, it is unlikely that there are many, if any, black dwarfs in our universe, which is only 12 to 18 billion years old. See Note at dwarf star.
white dwarf  
A small, extremely dense star characterized by high temperature and luminosity. A white dwarf is believed to be in its final stage of evolution, having either used up most of its nuclear fuel in its main-sequence stage, or else moved through a giant stage and shed any remaining fuel in its outer layer as a planetary nebula, leaving only a glowing core. Some 10 percent of all stars in the Milky Way are white dwarfs, but despite their intrinsic luminosity, they are so small that none are visible to the naked eye. See Note at dwarf.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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black dwarf in Culture

white dwarf definition

A kind of star about the size of the Earth. White dwarfs represent a final stage of the life cycle of stars similar to the sun; they are formed when the stars use up their fuel and can no longer support nuclear reactions.

The American Heritage® New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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