Any of a class of galaxies whose luminosity is greatest in radio wavelengths. Radio galaxies are usually large elliptical galaxies, with synchrotron radiation emitted from one or more pairs of lobes located on opposite sides of the visible galaxy.
usually an elliptical galaxy emitting very large amounts of radio energy from the core (up to millions of times a typical galaxy's radio emission) and having strong radio emission from regions extending out several million light years from the galaxy nucleus.
Type of active galaxy that emits most of its energy in the form of long-wavelength radiation.
a galaxy that is visible to radio telescopes
A galaxy that emits greater amounts of radio radiation than average.
A galaxy that emits radio waves from its central core. The energy to produce these emissions is generated by a supermassive black hole, which sends out massive jets of radio energy many millions of light-years into interstellar space.
a galaxy that emits an unusually large amount of radio waves
An active version of an elliptical galaxy, which is very bright in the radio spectrum at cosmological distances. M87 in Virgo is a well-known example.
A galactic system that emits prominently in radio wavelengths.
A galaxy that is extremely luminous at radio wavelengths. It is usually giant elliptical galaxy and a strong source of synchrotron radiation.
a galaxy showing unusually strong radio emission, too intense to be produced by the normal processes of starbirth and stardeath. This may come only from the nucleus, or from a pair of more or less symmetric lobes stretching as far as a million light-years. Many show emission from jets connecting the nucleus to these lobes. Optical spectra of radio galaxies may show nothing unusual, but in many instances show strong emission lines, either narrow (NLRG, like type 2 Seyferts) or including broad lines of certain species (BLRG, like quasars and type 1 Seyferts).
A particular type of active galaxy that emits more light at radio wavelengths than at visible wavelengths, also known as a radio-luminous galaxy or radio-loud galaxy. Radio galaxies are driven by non-thermal emission. Radio telescopes show that some radio galaxies, called extended radio galaxies, have lobes of radio emission extending millions of light-years from their nuclei. Centaurus A is a nearby example of an extended radio galaxy that features two outer lobes 650,000 and 1,350,000 light-years in diameter. In contrast, compact radio galaxies emit radio lobes not much larger than the galactic nucleus.
A radio galaxy is a galaxy that emits radio waves. Cygnus A is the most powerful radio galaxy close to Earth.
Radio galaxies and their relatives, radio-loud quasars and blazars, are types of active galaxy that are very luminous at radio wavelengths (up to 1038 W between 10 MHz and 100 GHz). The radio emission is due to the synchrotron process. The observed structure in radio emission is determined by the interaction between twin jets and the external medium, modified by the effects of relativistic beaming.
