UGC 11861

UGC 11861
The barred spiral galaxy UGC 11861, imaged by the Hubble Space Telescope
Observation data (J2000 epoch)
Constellation	Cepheus
Right ascension	21^h 56^m 24.0^s[1]
Declination	+73° 15′ 38.6″[1]
Redshift	0.004930[1]
Heliocentric radial velocity	1478 ± 1 km/s[1]
Distance	64.2 ± 4.5 Mly (19.68 ± 1.39 Mpc)[1]
Apparent magnitude (V)	15.2[1]
Characteristics
Type	SABdm[1]
Size	~94,300 ly (28.91 kpc) (estimated)[1]
Apparent size (V)	3.5' x 2.6'[1]
Other designations
IRAS 21557+7301, 2MASX J21562414+7315393, PGC 67671, CGCG 343-003[1]

UGC 11861 is a barred spiral galaxy in the constellation of Cepheus. Its velocity with respect to the cosmic microwave background is 1334 ± 10 km/s, which corresponds to a Hubble distance of 19.68 ± 1.39 Mpc (∼64.2 million light-years).[1] In addition, three non redshift measurements give a distance of 18.933 ± 5.26 Mpc (~61.7 million light-years).[2] The first known reference to this galaxy comes from volume IV of the Catalogue of Galaxies and of Clusters of Galaxies compiled by Fritz Zwicky in 1968, where it was listed as CGCG 343-003, and described as an "extremely diffuse spiral."[3]

The SIMBAD database lists UGC 11861 an active galaxy nucleus candidate, i.e. it has a compact region at the center that emits a significant amount of energy across the electromagnetic spectrum, with characteristics indicating that this luminosity is not produced by the stars.[4] In addition, the galaxy contains two broad spiral arms wrapping around its central region.[5]

Supernovae

Three supernovae have been observed in UGC 11861:

• SN 1995ag (type II, mag. 17) was discovered by Jean Mueller on 28 September 1995.[6][7]
• SN 1997db (Type II, mag. 16.9) was discovered by Michael Schwartz on 2 August 1997.[8][9]
• SN 2011dm (type Ia, mag. 18.8) was discovered by the Lick Observatory Supernova Search (LOSS) on 15 June 2011.[10][11]

References

1. "NASA/IPAC Extragalactic Database". Results for UGC 11861. Retrieved 19 August 2024.
2. "Distance Results for UGC 11861". NASA/IPAC EXTRAGALACTIC DATABASE. NASA. Retrieved 19 August 2024.
3. Zwicky, Fritz; Herzog, E. (1968). Catalogue of galaxies and of clusters of galaxies (PDF). Vol. IV. California Institute of Technology. pp. 214–215. Bibcode:1968cgcg.book.....Z. Archived from the original on August 19, 2023.
4. "UGC 11861". SIMBAD astronomical database. Strasbourg Astronomy Data Centre. Retrieved 19 August 2024.
5. [e-mail]. "A super(nova) spiral". www.esahubble.org. Retrieved 2024-08-20.
6. Mueller, J.; Griffith, D.; Brewer, C.; Mendenhall, J. D.; Reid, I. N.; Gizis, J. (1995). "Supernova 1995ag in UGC 11861". International Astronomical Union Circular (6244): 1. Bibcode:1995IAUC.6244....1M.
7. "SN 1995ag". Transient Name Server. IAU. Retrieved 19 August 2024.
8. Schwartz, M.; Offutt, W.; Filippenko, A. V.; Leonard, D. C.; Gilbert, A. M. (1997). "Supernova 1997db in UGC 11861". International Astronomical Union Circular (6711): 2. Bibcode:1997IAUC.6711....2O.
9. "SN 1997db". Transient Name Server. IAU. Retrieved 19 August 2024.
10. Kandrashoff, M.; Kelly, J.; Cenko, S. B.; Li, W.; Filippenko, A. V. (2011). "Supernova 2011dm in UGC 11861 = PSN J21564159+7317489". Central Bureau Electronic Telegrams. 2745: 1. Bibcode:2011CBET.2745....1K.
11. "SN 2011dm". Transient Name Server. IAU. Retrieved 19 August 2024.

External links

• Media related to PGC 67671 at Wikimedia Commons
• UGC 11861 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images