NGC 251

NGC 251
SDSS image of NGC 251
Observation data (J2000 epoch)
ConstellationPisces
Right ascension00h 47m 54.0517s
Declination+19° 35′ 48.788″
Redshift0.015184
Heliocentric radial velocity4556 km/s
Distance204.36 ± 12.64 Mly (62.657 ± 3.876 Mpc)
Apparent magnitude (B)14.6
Characteristics
TypeSc
Size149,300 ly (45,780 pc)
Apparent size (V)2.4′ × 1.9′
Other designations
KPG 015B, UGC 490, PGC 2806, CGCG 458-005

NGC 251 is a spiral galaxy in the constellation of Pisces. Its velocity with respect to the cosmic microwave background for is 4,224±23 km/s, which corresponds to a Hubble distance of 203.2 ± 14.3 Mly (62.30 ± 4.37 Mpc). Additionally, six non redshift measurements give a distance of 205.32 ± 5.54 Mly (62.950 ± 1.699 Mpc). It was discovered on October 15, 1784, by German-British astronomer William Herschel.

According to I.D. Karachentsev, NGC 251 forms an isolated galaxy pair with UGC 477.

One supernova has been observed in NGC 251: SN 2023rky (Type II, mag. 18.6) was discovered by the Zwicky Transient Facility on 6 September 2023.

Notes

  1. ↑ POSS1 103a-O values used.

See also

References

  1. 1 2 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.
  2. 1 2 3 4 5 6 7 "NED results for object NGC 0251". National Aeronautics and Space Administration / Infrared Processing and Analysis Center. Retrieved 5 May 2017.
  3. 1 2 "NGC 251". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 5 May 2017.
  4. ↑ "Distance Results for NGC 251". NASA/IPAC EXTRAGALACTIC DATABASE. NASA. Retrieved 9 April 2025.
  5. ↑ Seligman, Courtney. "New General Catalogue Objects: NGC 251". Celestial Atlas. Retrieved 9 April 2025.
  6. ↑ Karachentsev, I. D. (1972). "Catalogue of isolated pairs of galaxies in the northern hemisphere". Soobshcheniya Spetsial'noj Astrofizicheskoj Observatorii. 7: 1–92. Bibcode:1972SoSAO...7....1K.
  7. ↑ "SN 2023rky". Transient Name Server. IAU. Retrieved 9 April 2025.