3C 279 (also known as 4C–05.55, NRAO 413, and PKS 1253–05) is an optically violent variable quasar (OVV), which is known in the astronomical community for its variations in the visible,

radio Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmi ...

and

x-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...

bands. The quasar was observed to have undergone a period of extreme activity from 1987 until 1991. The Rosemary Hill Observatory (RHO) started observing 3C 279 in 1971, the object was further observed by the

Compton Gamma Ray Observatory The Compton Gamma Ray Observatory (CGRO) was a space observatory detecting photons with photon energy, energies from 20 kElectronvolt#Properties, eV to 30 GeV, in Earth orbit from 1991 to 2000. The observatory featured four main tele ...

in 1991, when it was unexpectedly discovered to be one of the brightest

gamma ray A gamma ray, also known as gamma radiation (symbol γ or \gamma), is a penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nuclei. It consists of the shortest wavelength electromagnetic waves, typically ...

objects in the sky.APOD: December 26, 1998 - Gamma Ray Quasar
/ref> It is also one of the brightest and most variable sources in the gamma ray sky monitored by the

Fermi Gamma-ray Space Telescope The Fermi Gamma-ray Space Telescope (FGST, also FGRST), formerly called the Gamma-ray Large Area Space Telescope (GLAST), is a space observatory being used to perform gamma-ray astronomy observations from low Earth orbit. Its main instrument is ...

. It was used as a calibrator source for

Event Horizon Telescope The Event Horizon Telescope (EHT) is a large Astronomical interferometer, telescope array consisting of a global network of radio telescopes. The EHT project combines data from several very-long-baseline interferometry (VLBI) stations around Ear ...

observations of M87* that resulted in the first image of a black hole.

Observations

* Apparent superluminal motion was detected during observations first made in 1973 in a jet of material departing from the quasar, though it should be understood that this effect is an optical illusion caused by naive estimations of the speed, and no truly superluminal motion is occurring. * 16 June 2015, the 3C 279 had a large gamma-ray outburst, believed to be caused by injection of high-speed electrons in central, high-density region. * Further observations with the Event Horizon Telescope during April 2017 provided a high level of detail to the radio jet, with a resolution as small as 20 micro-arcseconds. They indicated a bent or rotating jet shaped by shock waves.

Gallery

Artist’s impression of the quasar 3C 279

References

External links

* {{DEFAULTSORT:3C 279 OVV quasars 279 Virgo (constellation) ?