Seyfert galaxy

Class of active galaxies with very bright nuclei

Seyfert galaxies are one of the two largest groups of active galaxies, along with quasar host galaxies. They have quasar-like nuclei (very luminous sources of electromagnetic radiation that are outside of our own galaxy) with very high surface brightnesses whose spectra reveal strong, high-ionisation emission lines. However, unlike quasars, their host galaxies are clearly detectable.

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