3C 279

Virgo (constellation) NGC 4567 and NGC 4568 SN 2007bi
3C 279
Gamma-Ray Quasar 3C 279.jpg
Observation data (J2000 epoch)
Right ascension 12h 56m 11.1s[1]
Declination−05° 47′ 22″[1]
Redshift0.5362 ± 0.0004[1]
Distance5.0 Gly
Apparent magnitude (V)17.8[1]
Other designations
3C279 , 4C –05.55 , NRAO 413 , PKS 1253–05

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, and x-ray bands.[2] The quasar was observed to have undergone a period of extreme activity from 1987 until 1991.[3] The Rosemary Hill Observatory (RHO) started observing 3C 279 in 1971,[3] the object was further observed by the Compton Gamma Ray Observatory in 1991, when it was unexpectedly discovered to be one of the brightest gamma ray objects in the sky.[4] It is also one of the brightest and most variable sources in the gamma ray sky monitored by the Fermi Space Telescope. It was used as a calibrator source for Event Horizon Telescope observations of M87* that resulted in the first image of a black hole.[5]



Representative images of 3C 279 from EHT observations.
Artist's impression of the quasar 3C 279.


  1. ^ a b c d "NASA/IPAC Extragalactic Database". Results for 3C 279. Retrieved 2006-12-04.
  2. ^ Resonant absorption troughs in the gamma-ray spectra of QSO See section 4.2
  3. ^ a b J. R. Webb; M. T. Carini; S. Clements; S. Fajardo; P. P. Gombola; R. J. Leacock; et al. (1990). "The 1987-1990 optical outburst of the OVV quasar 3C 279". Astronomical Journal. 100: 1452–1456. Bibcode:1990AJ....100.1452W. doi:10.1086/115609.
  4. ^ APOD: December 26, 1998 - Gamma Ray Quasar
  5. ^ The Event Horizon Telescope Collaboration (10 April 2019). "First M87 Event Horizon Telescope Results. IV. Imaging the Central Supermassive Black Hole". The Astrophysical Journal. 875 (1): 22. doi:10.3847/2041-8213/ab1141. hdl:10150/633754.
  6. ^ Apparent superluminal motion
  7. ^ Singh, K. K.; Meintjes, P. J.; Ramamonjisoa, F. A. (2020). "Understanding the giant gamma-ray outburst on June 16, 2015 from the blazar 3C 279". Astrophysics and Space Science. 365 (2): 33. arXiv:2002.04965. Bibcode:2020Ap&SS.365...33S. doi:10.1007/s10509-020-3746-2.
  8. ^ Kim, Jae-Young; et al. (EHT) (April 7, 2020). "Event Horizon Telescope imaging of the archetypal blazar 3C 279 at an extreme 20 microarcsecond resolution" (PDF). Astronomy & Astrophysics. doi:10.1051/0004-6361/202037493. Retrieved April 8, 2020.