quasar
one of over a thousand known extragalactic objects, starlike in appearance and having spectra with characteristically large redshifts, that are thought to be the most distant and most luminous objects in the universe.
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Origin of quasar
1- Also called quasi-stellar object.
Words Nearby quasar
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024
How to use quasar in a sentence
With quasar research, it was just too fast, and she wanted to be methodical about it.
Vera Rubin’s work on dark matter led to a paradigm shift in cosmology | Maria Temming | August 17, 2021 | Science NewsThe quasar light absorbed by those atoms traces out a nearly symmetrical curve of dozens of galaxies spanning about one-fifteenth the radius of the observable universe, Lopez reported.
An arc of galaxies 3 billion light-years long may challenge cosmology | Lisa Grossman | June 10, 2021 | Science NewsBoth ACT and Planck disagree with most estimates from objects that emitted their light more recently, such as exploding stars called supernovas and bright hearts of galaxies known as quasars.
Despite a new measurement, the debate over the universe’s expansion rages on | Emily Conover | July 15, 2020 | Science NewsMost quasars that astronomers and others have found are billions of light-years away from Earth.
Because quasars are so far way, people need telescopes to see them.
The direction of polarization for a quasar is determined by the accretion disk surrounding it.
British Dictionary definitions for quasar
/ (ˈkweɪzɑː, -sɑː) /
any of a class of extragalactic objects that emit an immense amount of energy in the form of light, infrared radiation, etc, from a compact source. They are extremely distant and their energy generation is thought to involve a supermassive black hole located in the centre of a galaxy
Origin of quasar
1Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for quasar
[ kwā′zär′ ]
Short for quasi-stellar radio source. A compact, starlike celestial body with a power output greater than our entire galaxy. Believed to be the oldest and most distant objects ever detected, quasars are billions of light-years from Earth and moving away from us at nearly 80 percent of the speed of light. For this reason, quasars are highly important to astronomers' understanding of the early universe. Little is currently understood about the nature of quasars; one theory suggests that they are produced by giant black holes destroying enormous amounts of matter, causing the subsequent ejection of radiation along their north and south poles. Many astronomers believe that quasars represent an early stage in the evolution of galaxies such as our own. See also blazar Seyfert galaxy.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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