NGC 925

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NGC 925
NGC925.jpg
NGC 925 imaged with the 32 inch telescope at Mount Lemmon Observatory, courtesy Joseph D. Schulman
Observation data (J2000 epoch)
Constellation Triangulum
Right ascension 02h 27m 16.913s[1]
Declination +33° 34′ 43.97″[1]
Redshift 553 ± 3 km/s[2]
Helio radial velocity 564[3] km/s
Distance 30.3 ± 2.3 million light years (9.29 ± 0.69 Mpc)[4]
Group or cluster NGC 1023 Group[5]
Type SB(s)d[3]
Apparent dimensions (V) 10′.5 × 5′.9[2]
Apparent magnitude (V) 10.7[2]
Other designations
PGC 009332, UGC 01913[2]
See also: Galaxy, List of galaxies
NGC925HunterWilson.jpg

NGC 925 is a barred spiral galaxy located about 30[4] million light-years away in the constellation Triangulum. The morphological classification of this galaxy is SB(s)d,[3] which indicates that this has a bar structure and loosely wound spiral arms with no ring.[6] The spiral arm to the south is stronger than the northern arm, with the latter appearing flocculent and less coherent. The bar is offset from the center of the galaxy and is the site of star formation all along its length. Both of these morphological traits—a dominant spiral arm and the offset bar—are typically characteristics of a Magellanic spiral galaxy.[7] The galaxy is inclined at an angle of 55° to the line of sight along a position angle of 102°.[3]

This galaxy is a member of the NGC 1023 Group, a nearby, gravitationally-bound group of galaxies associated with NGC 1023.[5] However, the nearest member lies at least 650,000 ly (200,000 pc) distant from NGC 925. There is a 10 million solar mass (M) cloud of neutral hydrogen attached to NGC 925 by a streamer. It is uncertain whether this is a satellite dwarf galaxy, the remnant of a past tidal interaction, or a cloud of primordial gas.[8]

References[edit]

  1. ^ a b Skrutskie, M. F. et al. (February 2006), "The Two Micron All Sky Survey (2MASS)", Astrophysical Journal 131 (2): 1163–1183, Bibcode:2006AJ....131.1163S, doi:10.1086/498708. 
  2. ^ a b c d "NASA/IPAC Extragalactic Database". Results for NGC 925. Retrieved 2008-12-28. 
  3. ^ a b c d Martin, Pierre; Roy, Jean-Rene (April 1994), "The influence of bars on the chemical composition of spiral galaxies", Astrophysical Journal, Part 1 424 (2): 599–614, Bibcode:1994ApJ...424..599M, doi:10.1086/173917. 
  4. ^ a b Silbermann, N. A. et al. (October 1996), "The Hubble Space Telescope Key Project on the Extragalactic Distance Scale. VI. The Cepheids in NGC 925", Astrophysical Journal 470: 1, Bibcode:1996ApJ...470....1S, doi:10.1086/177845. 
  5. ^ a b Tully, R. B. (April 1980), "Nearby groups of galaxies. I - The NGC 1023 group", Astrophysical Journal, Part 1 237: 390–403, Bibcode:1980ApJ...237..390T, doi:10.1086/157881. 
  6. ^ Buta, Ronald J. et al. (2007), Atlas of Galaxies, Cambridge University Press, pp. 13–17, ISBN 0521820480. 
  7. ^ Pisano, D. J.; Wilcots, Eric M.; Elmegreen, Bruce G. (August 2000), "Structure and Star Formation in NGC 925", The Astronomical Journal 120 (2): 763–776, arXiv:astro-ph/0004219, Bibcode:2000AJ....120..763P, doi:10.1086/301464. 
  8. ^ Pisano, D. J. et al. (June 2007), "An H I Survey of Six Local Group Analogs. I. Survey Description and the Search for High-Velocity Clouds", The Astrophysical Journal 662 (2): 959–968, arXiv:astro-ph/0703279, Bibcode:2007ApJ...662..959P, doi:10.1086/517986. 

Coordinates: Sky map 02h 27m 16.9s, +33° 34′ 45″