NGC 2857

"Arp 1" redirects here. For the star cluster with that name, see Palomar 14.

NGC 2857
SDSS image of NGC 2857
Observation data (J2000 epoch)
Constellation	Ursa Major[1]
Right ascension	09^h 24^m 37.698^s [2]
Declination	+49° 21′ 25.69″ [2]
Redshift	0.016301 ± 0.000023 [3]
Heliocentric radial velocity	4887 ± 7 km/s [3]
Galactocentric velocity	4917 ± 7 km/s [3]
Distance	69.050 ± 00 Mpc (225.21 ± 0.00 Mly)h^−1 0.73 [3]
Apparent magnitude (V)	12.27 [2]
Apparent magnitude (B)	12.90 [2]
Absolute magnitude (V)	-21.92 ± 0.22 [3]
Characteristics
Type	SA(s)c [3]
Size	125,000 [1]
Apparent size (V)	1.70′ × 1.43′ [3]
Other designations
NGC 2857, Arp 1, APG 1, PGC 26666, UGC 5000

NGC 2857 (also known as Arp 1 and PGC 26666) is a spiral galaxy in the constellation Ursa Major. It was discovered on January 9, 1856, by R. J. Mitchell.^[1]

NGC 2857 is the first object in Halton Arp's Atlas of Peculiar Galaxies, and one of six Arp objects in the 'Low Surface Brightness Galaxies' section. The other five low surface brightness galaxies are Arp 2 (UGC 10310), Arp 3, Arp 4, Arp 5 (NGC 3664), and Arp 6 (NGC 2537).^[4]

Supernova

One supernova has been observed in NGC 2857:

• SN 2012fg (Type II-P, mag. 14.5) was discovered by the MASTER-Kislovodsk auto-detection system on October 7, 2012.^[5][6][7][8] Its absolute magnitude was calculated to be -19.8.^[9] The spectrum of SN 2012fg was recorded and analyzed by multiple teams of scientists as it changed rapidly in the days following its detection.^[10][11]

References

1. Seligman, Courtney. "New General Catalog Objects: NGC 2850 - 2899". Retrieved 2015-11-29.
2. "SIMBAD Astronomical Database". Results for NGC 2857. Retrieved 2015-11-29.
3. "NASA/IPAC Extragalactic Database". Results for NGC 2857. Archived from the original on 1997-12-22. Retrieved 2015-11-29.
4. Arp, Halton (1966). "Atlas of Peculiar Galaxies". Retrieved 2015-11-25.
5. Lipunov, V.; Shumkov, V.; Denisenko, D.; Gorbovskoy, E.; Elenin, L.; Molotov, I.; Camilleri, P.; Marion, G. H.; Vinko, J. (2012). "Supernova 2012fg in NGC 2857 = PSN J09243795+4921320". Central Bureau Electronic Telegrams (3253): 1. Bibcode:2012CBET.3253....1L.
6. "SN 2012fg". Transient Name Server. IAU. Retrieved 17 December 2025.
7. Pruzginskaya, M.; et al. (2012). "Folow up [sic] B,V,R,I photometry bright SN 2012fg in NGC 2857 discovered by MASTER". The Astronomer's Telegram. 4489: 1. Bibcode:2012ATel.4489....1P.
8. Shumkov, V.; et al. (2012). "Bright PSN in NGC2857". The Astronomer's Telegram. 4459: 1. Bibcode:2012ATel.4459....1S.
9. Cellier-Holzem, F.; et al. (2012). "Spectroscopic Observation of the Bright PSN in NGC2857 by the Nearby Supernova Factory II". The Astronomer's Telegram. 4466: 1. Bibcode:2012ATel.4466....1C.
10. Fabrika, S.; Valeev, A.; Fatkhullin, T.; Sholukhova, O.; Vinokurov, A. (2012). "Spectrum of bright SN 2012fg in NGC 2857". The Astronomer's Telegram. 4496: 1. Bibcode:2012ATel.4496....1F.
11. Fabrika, S.; Fatkhullin, T.; Valeev, A.; Moskvitin, A.; Vinokurov, A.; Sholukhova, O. (2012). "Spectrum change of bright SN 2012fg in NGC 2857". The Astronomer's Telegram. 4520: 1. Bibcode:2012ATel.4520....1F.

External links

• Media related to NGC 2857 at Wikimedia Commons
• Full Arp Atlas
• Halton Arp's image of Arp 1
• Constellation Locator
• SIMBAD Astronomical Database
• NASA/IPAC Extragalactic Database
• SN 2012fg detection announcement