Самый яркий квазар 3C 273 в созвездии Девы

Brightest quasar from Earth located in the constellation Virgo
Given its distance from Earth and visual magnitude, 3C 273 is the most distant celestial object average amateur astronomers are likely to see through their telescopes.

This is the optically brightest quasar in the sky from Earth with an apparent visual magnitude of ~12.9, and one of the closest with a redshift, z, of 0.158. Using parallax methods with the Very Large Telescope interferometer yields a distance estimate of 1.80 (552). meaning that if it were only as distant as Pollux (~10 parsecs) it would appear nearly as bright in the sky as the Sun. Since the Sun's absolute magnitude is 4.83, it means that the quasar is over 4 trillion times more luminous than the Sun at visible wavelengths. The luminosity of 3C 273 is variable at nearly every wavelength from radio waves to gamma rays on timescales of a few days to decades. Polarization with coincident orientation has been observed with radio, infrared, and optical light being emitted from a large scale jet; these emissions are therefore almost certainly synchrotron in nature. This is a prototype of an Active Galactic Nucleus, demonstrating that the energy is being produced through accretion by a supermassive black hole (SMBH). No other astrophysical source can produce the observed energy. The mass of its central SMBH has been measured to be 886 million solar masses through broad emission line reverberation mapping.

The quasar has a large scale visible jet, which measures ~ long, having an apparent size of 23″. An expanding cocoon of heated gas is being generated by the jet, which may be impacting an inclined disk of gas within the central 6. indicating a moderately flattened elliptical shape. The galaxy has an estimated mass of 2.

The name signifies that it was the 273rd object (ordered by right ascension) of the Third Cambridge Catalog of Radio Sources (3C), published in 1959. After accurate positions were obtained using lunar occultation by Cyril Hazard at the Parkes Radio Telescope, the radio source was quickly associated with an optical counterpart, an unresolved stellar object. In 1963, Maarten Schmidt and Bev Oke published a pair of papers in Nature reporting that 3C 273 has a substantial redshift of 0.158, placing it several billion light years away. Prior to the discovery of 3C 273, several other radio sources had been associated with optical counterparts, the first being 3C 48. Also, many active galaxies had been misidentified as variable stars, including the famous BL Lac, W Com and AU CVn. However, it was not understood what these objects were, since their spectra were unlike those of any known stars. Its spectrum did not resemble that of any normal stars with typical stellar elements. 3C 273 was the first object to be identified as a quasar—an extremely luminous object at an astronomical distance. 3C 273 is a radio loud quasar, and was also one of the first extragalactic X ray sources discovered in 1970. However, even to this day, the process which gives rise to the X ray emissions is controversial.