quasar
[ kwey-zahr, -zer, -sahr, -ser ]
/ ˈkweɪ zɑr, -zər, -sɑr, -sər /
noun Astronomy.
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.
Also called
quasi-stellar object.
Origin of quasar
1960–65;
quas(i-stell)ar, in
quasi-stellar radio source, the first type of quasar discovered
Words nearby quasar
quartz movement,
quartz plate,
quartz-iodine lamp,
quartziferous,
quartzite,
quasar,
quasars,
quash,
quasheba,
quashee,
quashi
Example sentences from the Web for quasar
The direction of polarization for a quasar is determined by the accretion disk surrounding it.
British Dictionary definitions for quasar
quasar
/ (ˈkweɪzɑː, -sɑː) /
noun
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
Word Origin for quasar
C20:
quas (
i-stell)
ar (
object)
Scientific definitions for quasar
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.