black dwarf
Americannoun
-
black dwarfs
plural
-
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
Other Word Forms
Noun Inflected Forms
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Earth's sun will eventually end its life as a white, then black, dwarf.
From Salon ● Jan. 9, 2023
However, astrophysicists calculate that this type of star, known as a black dwarf, would take so long to cool that there are not yet any black dwarf stars anywhere in the entire universe.
From Salon ● Jan. 9, 2023
As the millenniums pass, the white dwarf gradually loses its heat, turning first yellow, then red; eventually, its fires burn out entirely, leaving behind a "black dwarf," a cold cinder in the graveyard of space.
From Time Magazine Archive
In the portraits of the ladies who belonged to that dissolute court managed by Louis XIV of France, there often appears the dark and ambiguous figure of a black dwarf.
From Time Magazine Archive
Then he lit his pipe at the blue light, and the black dwarf was before him in a moment.
From Children's Literature A Textbook of Sources for Teachers and Teacher-Training Classes by Erle Elsworth Clippinger
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
