NGC 6251 | |
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Observation data (J2000 epoch) | |
Constellation | Ursa Minor |
Right ascension | 16h 32m 31.9700s[1] |
Declination | +82° 32′ 16.400″[1] |
Redshift | 0.02471[1] |
Distance | 340 million light-years[2] |
Apparent magnitude (V) | 14.3[3] |
Characteristics | |
Type | E[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]