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NGC 1808 - Wikipedia

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NGC 1808
A Hubble Space Telescope (HST) image of NGC 1808 taken using WFPC2.^[1]
Observation data (J2000 epoch)
Constellation	Columba^[2]
Right ascension	05^h 07^m 42.343^s^[3]
Declination	−37° 30′ 46.98″^[3]
Redshift	995^[4]
Distance	41.7 ± 3.9 Mly (12.8 ± 1.2 Mpc)^[5]
Group or cluster	Dorado Group
Apparent magnitude (V)	9.94^[6]
Apparent magnitude (B)	10.83^[4]
Absolute magnitude (B)	−20.17^[7]
Characteristics
Type	(R)SAB(s)a^[7]
Apparent size (V)	7′.41 × 3′.39^[8]
Other designations
PGC 16779^[9]

NGC 1808 is a barred spiral galaxy^[5] located in the southern constellation of Columba, about two degrees to the south and east of Gamma Caeli.^[2] It was discovered by Scottish astronomer James Dunlop, who described it as a "faint nebula".^[10] The galaxy is a member of the NGC 1808 group, which is part of the larger Dorado Group.^[10]

The morphological classification of this galaxy is (R)SAB(s)a,^[7] which indicates a spiral galaxy with a weak-bar around the nucleus (SAB), no ring around the bar (s), an outer ring (R), and tightly-wound spiral arms (a). It is inclined by an angle of 57° to the line of sight from the Earth, with the long axis oriented at a position angle of 324°.^[5] The disk of gas and stars shows a noticeable warp, and there is a pronounced asymmetry in the distribution of neutral hydrogen and H II regions.^[11]

The core region contains a suspected weak active galactic nucleus plus a circumnuclear ring containing star clusters and supernova remnants at a distance of ~280 pc from the center. These form a ring of peculiar "hot spots".^[12] It was formerly identified as a possible Seyfert galaxy,^[5] but evidence now points to starburst activity in a ~500 pc radius around the center.^[13] A probable outflow of gas is directed to the north-east from the nucleus, forming prominent dust lanes.^[5] The high level of star formation in this galaxy and the nearby NGC 1792 may indicate a recent, distant tidal interaction between the two.^[11]

The type Ia supernova SN 1993af was discovered in November 1993 at 220″ east and 94″ north of the galactic nucleus.^[14]^[15]

References

^ "HubbleSite - NewsCenter - Hubble Captures the Heart of Star Birth". Retrieved 2007-04-05.
^ ^a ^b Sinnott, Roger W.; Perryman, Michael A. C. (1997). Millennium Star Atlas. Vol. 1. Sky Publishing Corporation and the European Space Agency. ISBN 0-933346-84-0.
^ ^a ^b Skrutskie, Michael F.; et al. (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 Tully, R. Brent; et al. (August 2016). "Cosmicflows-3". The Astronomical Journal. 152 (2): 21. arXiv:1605.01765. Bibcode:2016AJ....152...50T. doi:10.3847/0004-6256/152/2/50. S2CID 250737862. 50.
^ ^a ^b ^c ^d ^e Busch, Gerold; et al. (February 2017). "Star formation and gas flows in the centre of the NUGA galaxy NGC 1808 observed with SINFONI". Astronomy & Astrophysics. 598: 19. arXiv:1611.07868. Bibcode:2017A&A...598A..55B. doi:10.1051/0004-6361/201629440. S2CID 118950569. A55.
^ Armando, Gil de Paz; et al. (2007). "The GALEX Ultraviolet Atlas of Nearby Galaxies". Astrophysical Journal. 173 (2): 185–255. arXiv:astro-ph/0606440. Bibcode:2007ApJS..173..185G. doi:10.1086/516636. S2CID 119085482.
^ ^a ^b ^c Erwin, Peter; Debattista, Victor P. (June 2013). "Peanuts at an angle: detecting and measuring the three-dimensional structure of bars in moderately inclined galaxies". Monthly Notices of the Royal Astronomical Society. 431 (4): 3060–3086. arXiv:1301.0638. Bibcode:2013MNRAS.431.3060E. doi:10.1093/mnras/stt385.
^ Paturel, G.; et al. (December 2003). "HYPERLEDA. I. Identification and designation of galaxies". Astronomy and Astrophysics. 412: 45–55. Bibcode:2003A&A...412...45P. doi:10.1051/0004-6361:20031411.
^ "NASA/IPAC Extragalactic Database". Results for NGC 1808. Retrieved 2007-04-05.
^ ^a ^b O'Meara, Stephen James (2013), Deep-Sky Companions: Southern Gems, Cambridge University Press, p. 116, Bibcode:2013dcsg.book.....O, ISBN 978-1107015012
^ ^a ^b Dahlem, M.; et al. (July 2001). "A search for intergalactic H I gas in the NGC 1808 group of galaxies". Astronomy and Astrophysics. 373 (2): 485–493. arXiv:astro-ph/0106050. Bibcode:2001A&A...373..485D. doi:10.1051/0004-6361:20010614. S2CID 15512721.
^ Salak, Dragan; et al. (May 2016). "Gas Dynamics and Outflow in the Barred Starburst Galaxy NGC 1808 Revealed with ALMA". The Astrophysical Journal. 823 (1): 28. arXiv:1603.05881. Bibcode:2016ApJ...823...68S. doi:10.3847/0004-637X/823/1/68. S2CID 118634377. 68.
^ Salak, Dragan; et al. (November 2017). "Evolution of Molecular Clouds in the Superwind Galaxy NGC 1808 Probed by ALMA Observations". The Astrophysical Journal. 849 (2): 20. arXiv:1710.01829. Bibcode:2017ApJ...849...90S. doi:10.3847/1538-4357/aa91cb. S2CID 119456694. 90.
^ Hamuy, M.; et al. (November 1993). Green, D. W. E. (ed.). "Supernovae 1993af, 1993ag, 1993ah". IAU Circular. 5895: 1. Bibcode:1993IAUC.5895....1H.
^ Hamuy, M.; et al. (December 1996). "BVRI Light Curves for 29 Type IA Supernovae". Astronomical Journal. 112: 2408. arXiv:astro-ph/9609064. Bibcode:1996AJ....112.2408H. doi:10.1086/118192. S2CID 119520520.

External links

Media related to NGC 1808 at Wikimedia Commons
Pictures and description at Hubble Heritage website

v t e Astronomical catalogs
NGC	NGC 1803 NGC 1804 NGC 1805 NGC 1806 NGC 1807 NGC 1808 NGC 1809 NGC 1810 NGC 1811 NGC 1812 NGC 1813
PGC	PGC 16775 PGC 16776 PGC 16777 PGC 16778 PGC 16779 PGC 16780 PGC 16781 PGC 16782 PGC 16783

New General Catalogue 1500 to 1999

Constellation of Columba

Stars

Bayer	α (Phact) β (Wazn) γ δ ε η θ (Elkurud) κ λ (Tsze) μ ν¹ ν² ξ ο π¹ π² σ
Variable	WZ AF AP
HR	1721 1758 1835 1877 1958 2069 2082 2131 2149 2263 2288 2399 2411 2445 2446
HD	43848
Other	NGTS-1 NGTS-3 WASP-63

Exoplanets	NGTS-1b NGTS-3Ab NGTS-4b WASP-63b

Star clusters	NGC 1851

Galaxies

NGC	1792 1808 1989 1992 2090
Other	ESO 306-17 PKS 0521-365