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NGC 6251
NGC 6251HST.jpg
Hubble image of the heart of the active galaxy NGC 6251
Observation data ( J2000 epoch)
Constellation Ursa Minor
Right ascension16h 32m 31.9700s [1]
Declination+82° 32′ 16.400″ [1]
Redshift0.02471 [1]
Distance340 million light-years [2]
Apparent magnitude (V)14.3 [3]
TypeE [1]
Apparent size (V)1.82´X1.55´
Other designations
NGC 6251, UGC 10501, LEDA 58472, 6C 1636+8239, QSO B1637+826

NGC 6251 is an active supergiant elliptical radio galaxy in the constellation Ursa Minor, and is more than 340 million light-years away from Earth. The galaxy has a Seyfert 2 active galactic nucleus, [3] and is one of the most extreme examples of a Seyfert galaxy. This galaxy may be associated with gamma-ray source 3EG J1621+8203, which has high-energy gamma-ray emission. [3] It is also noted for its one-sided radio jet—one of the brightest known—discovered in 1977. [4] The supermassive black hole at the core has a mass of (5.9±2.0)×108  M. [5]


  1. ^ a b c d "NASA/IPAC Extragalactic Database". Results for NGC 6251. Retrieved 2006-10-26.
  2. ^ "Distance and Length". Archived from the original on 2010-03-30. Retrieved 2010-03-29.
  3. ^ a b c SIMBAD
  4. ^ Perley, R. A.; Bridle, A. H.; Willis, A. G. (1984). "High-resolution VLA Observations of the Radio Jet in NGC 6251". Astrophysical Journal Supplement Series. 54: 291–334. Bibcode: 1984ApJS...54..291P. doi: 10.1086/190931.
  5. ^ Graham, Alister W. (November 2008), "Populating the Galaxy Velocity Dispersion - Supermassive Black Hole Mass Diagram: A Catalogue of (Mbh, σ) Values", Publications of the Astronomical Society of Australia, 25 (4): 167–175, arXiv: 0807.2549, Bibcode: 2008PASA...25..167G, doi: 10.1071/AS08013, S2CID  89905.

External links

NGC 6251 R814B547.png