quasar

[ kwey-zahr, -zer, -sahr, -ser ]

noun

, Astronomy.

1. 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.

quasar

/ ˈkweɪzɑː; -sɑː /

noun

1. 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

quasar

/ kwā′zär′ /

1. 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.
2. See also blazar

Word History and Origins

Origin of quasar¹

1960–65; quas(i-stell)ar, in quasi-stellar radio source, the first type of quasar discovered

Word History and Origins

Origin of quasar¹

C20: quas ( i-stell ) ar ( object )

Example Sentences

With quasar research, it was just too fast, and she wanted to be methodical about it.

From Science News

The 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.

From Science News

Both 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.

From Science News

Most quasars that astronomers and others have found are billions of light-years away from Earth.

From Science News For Students

Because quasars are so far way, people need telescopes to see them.

From Science News For Students

The direction of polarization for a quasar is determined by the accretion disk surrounding it.

From The Daily Beast