Okuzeka
Astronomy & Space vocabulary · Galaxies & Deep Sky

Quasar

Meaning in astronomy & space, with examples

/ˈkweɪzɑːr/nounAdvanced term

In astronomy & space, quasar means: The extremely bright centre of a distant galaxy, powered by a supermassive black hole pulling in gas. A single quasar can outshine its entire galaxy.

In Turkish: kuasar

How it is used

The name is short for 'quasi-stellar object', because quasars first looked like stars in telescopes. Astronomers use them to study the early universe and the gas between galaxies. They belong to the wider class of active galactic nuclei (AGN).

Example sentences

  1. The light from this quasar left it more than 12 billion years ago.

  2. Quasars were most common when the universe was a few billion years old.

Common collocations

  • distant quasar
  • bright quasar
  • quasar activity
  • active galactic nucleus
  • supermassive black holeA black hole with the mass of millions or billions of Suns. Almost every large galaxy, including the Milky Way, has one at its centre.
  • galaxyAn enormous system of stars, gas, dust and dark matter held together by gravity. A large galaxy can contain hundreds of billions of stars.
  • redshiftThe stretching of light from an object that is moving away from us or whose light crosses expanding space, so that its spectral lines shift to longer, redder wavelengths.
  • black holeA region of space where matter is packed so tightly that gravity stops anything, even light, from escaping. Many form when very massive stars collapse.

More terms: Galaxies & Deep Sky

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