Astrophysics (Index)About

Cygnus A

(3C 405, QSO B1957+405)
(early-discovered radio galaxy showing a quasar)

Cygnus A (i.e., 3C 405 or QSO B1957+405) is a radio galaxy, one of the first identified. As a radio source, it was discovered by Grote Reber in 1938, with his back-yard radio telescope, the first radio receiver built for that purpose. An apparent quasar was discovered within it in the 1990s: this is no mystery since quasars are interpreted as active galactic nuclei, which are also often the driver for strong radio emission from galaxies. Cygnus A demonstrates the involvement of jets in creating a radio galaxy's radio emission; its strongest radio signal comes from two regions in opposite directions from the galaxy itself.

Further reading:
/Lookback Years
.056232Mpc757MlyCygnus A
Coordinates:3C 405

Referenced by page:
quasar (QSO)