Seyfert galaxy

[sahy-fert, see-]
noun Astronomy.
  1. one of a group of spiral galaxies with compact, bright nuclei having characteristically broad emission lines suggestive of very hot gases in violent motion at the center.

Origin of Seyfert galaxy

1965–70; named after Carl K. Seyfert (1911–60), American astronomer, who first described them
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British Dictionary definitions for seyfert galaxy

Seyfert galaxy

noun
  1. any of a class of spiral galaxies having a very bright nucleus, possibly corresponding to an active period in the lives of all spiral galaxies

Word Origin for Seyfert galaxy

C20: named after Carl K. Seyfert (died 1960), US astronomer
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

seyfert galaxy in Science

Seyfert galaxy

[sēfərt, sī-]
  1. A spiral galaxy with a small, compact, bright nucleus that exhibits variable light intensity and radio-wave emission. Seyfert galaxies are active galaxies and are thought to contain a black hole in their galactic nucleus. The nuclei of Seyfert galaxies generate an emission spectrum characteristic of hot, ionized clouds of gas, shooting out from the accretion disk around the black hole. The observations during the 1940s of American astronomer Carl Seyfert (1911-60), after whom the galaxies are named, demonstrated that these jets of gas are expelled from the nucleus at speeds up to millions of miles per hour. See also blazar quasar.
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