| NGC 251 | |
|---|---|
 SDSS image of NGC 251 | |
| Observation data (J2000 epoch) | |
| Constellation | Pisces |
| Right ascension | 00h 47m 54.031s[1] |
| Declination | +19° 35′ 48.51″[1] |
| Redshift | 0.015184[2] |
| Heliocentric radial velocity | 4552 km/s[2] |
| Distance | 204.36 ± 12.64 Mly (62.657 ± 3.876 Mpc)[2] |
| Apparent magnitude (B) | 14.6[3] |
| Characteristics | |
| Type | Sc[2] |
| Size | 148,600 ly (45,570 pc)[2][note 1] |
| Apparent size (V) | 2.4′ × 1.9′[2] |
| Other designations | |
| UGC 490, MGC+03-03-003, PGC 2806[3] | |
NGC 251 is a spiral galaxy in the constellation of Pisces. It was discovered on October 15, 1784, by Frederick William Herschel.
One supernova has been observed in NGC 251: SN 2023rky (type II, mag. 18.6).[4]
- ^ a b Skrutskie, Michael F.; Cutri, Roc M.; Stiening, Rae; Weinberg, Martin D.; Schneider, Stephen E.; Carpenter, John M.; Beichman, Charles A.; Capps, Richard W.; Chester, Thomas; Elias, Jonathan H.; Huchra, John P.; Liebert, James W.; Lonsdale, Carol J.; Monet, David G.; Price, Stephan; Seitzer, Patrick; Jarrett, Thomas H.; Kirkpatrick, J. Davy; Gizis, John E.; Howard, Elizabeth V.; Evans, Tracey E.; Fowler, John W.; Fullmer, Linda; Hurt, Robert L.; Light, Robert M.; Kopan, Eugene L.; Marsh, Kenneth A.; McCallon, Howard L.; Tam, Robert; Van Dyk, Schuyler D.; Wheelock, Sherry L. (1 February 2006). "The Two Micron All Sky Survey (2MASS)". The Astronomical Journal. 131 (2): 1163–1183. Bibcode:2006AJ....131.1163S. doi:10.1086/498708. ISSN 0004-6256. S2CID 18913331.
- ^ a b c d e f "NED results for object NGC 0251". National Aeronautics and Space Administration / Infrared Processing and Analysis Center. Retrieved 5 May 2017.
- ^ a b "NGC 251". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 5 May 2017.
- ^ Transient Name Server entry for SN 2023rky. Retrieved 7 September 2023.
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