Astronomy:NGC 959

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Short description: Spiral galaxy in the northern constellation of Triangulum
NGC 959
NGC 959 -HST09042 14-R814GB435.png
Observation data (J2000 epoch)
ConstellationTriangulum
Right ascension 02h 32m 23.923s[1]
Declination+35° 29′ 40.46″[1]
Helio radial velocity596 km/s[2]
Distance36 Mly (11.0 Mpc)[2][3]
Group or clusterNGC 1023 Group[4]
Apparent magnitude (V)12.38±0.14[3]
Apparent magnitude (B)12.95±0.14[3]
Characteristics
TypeSdm:[3] or SBcd[5]
Mass6.3×108[6] (stellar) M
Size21.8 kly (6.69 kpc)[7]
Apparent size (V)2′.3 × 1′.4[3] (D25)
Other designations
IRAS 02293+3516, NGC 959, UGC 2002, MCG+06-06-051, PGC 9665[8][9]

NGC 959 is a spiral galaxy in the northern constellation of Triangulum.[10] It was discovered on November 9, 1876, by French astronomer Édouard Stephan.[9] This galaxy is located at a distance of 36 million light years and is receding with a heliocentric radial velocity of 596 km/s.[2] It is a member of the NGC 1023 Group of galaxies.[4]

The morphological class of this galaxy is Sdm:,[3] indicating it is a spiral (S) with disorganized, irregular arms and no central bulge (dm). The ':' suffix indicates some uncertainty about the classification. It has a visual magnitude of 12.4.[3] The galactic plane is inclined at an angle of 50° to the line of sight from the Earth,[11] giving it an elliptical profile with the major axis aligned along a position angle of 65°. The size of the D25 ellipse (where the brightness of the galaxy drops to magnitude 25) is 2.3 × 1.4 arcminutes.[3]

When images of NGC 959 are corrected for the effects of extinction from dust, a central bar feature can be discerned. The galaxy then shows a non-negligible bulge or central condensation, and may instead have a morphological type of SBcd.[5] It displays a cuspy central density profile and bulge-like monotonic decrease in ellipticity toward the core.[6]

References

  1. 1.0 1.1 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  2. 2.0 2.1 2.2 Tully, R. Brent et al. (August 2016), "Cosmicflows-3", The Astronomical Journal 152 (2): 21, doi:10.3847/0004-6256/152/2/50, 50, Bibcode2016AJ....152...50T. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 Gil de Paz, Armando et al. (December 2007), "The GALEX Ultraviolet Atlas of Nearby Galaxies", The Astrophysical Journal Supplement Series 173 (2): 185–255, doi:10.1086/516636, Bibcode2007ApJS..173..185G. 
  4. 4.0 4.1 Trentham, Neil; Tully, R. Brent (September 2009), "Dwarf galaxies in the NGC 1023 Group", Monthly Notices of the Royal Astronomical Society 398 (2): 722–734, doi:10.1111/j.1365-2966.2009.15189.x, Bibcode2009MNRAS.398..722T. 
  5. 5.0 5.1 Tamura, K. et al. (June 2010), "Lifting the Veil of Dust from NGC 0959: The Importance of a Pixel-based Two-dimensional Extinction Correction", The Astronomical Journal 139 (6): 2557–2565, doi:10.1088/0004-6256/139/6/2557, Bibcode2010AJ....139.2557T. 
  6. 6.0 6.1 Relatores, Nicole C. et al. (December 2019), "The Dark Matter Distributions in Low-mass Disk Galaxies. II. The Inner Density Profiles", The Astrophysical Journal 887 (1): 23, doi:10.3847/1538-4357/ab5305, 94, Bibcode2019ApJ...887...94R. 
  7. Truong, Phuongmai N. et al. (July 2017), "High-resolution Velocity Fields of Low-mass Disk Galaxies. I. CO Observations", The Astrophysical Journal 843 (1): 15, doi:10.3847/1538-4357/aa76eb, 37, Bibcode2017ApJ...843...37T, https://discovery.ucl.ac.uk/id/eprint/10041323/. 
  8. "NGC 959". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=NGC+959. 
  9. 9.0 9.1 Seligman, Courtney, NGC Objects: NGC 950 - 999, https://cseligman.com/text/atlas/ngc9a.htm#959, retrieved 2022-01-18. 
  10. Aranda, Ted (2011), 3,000 Deep-Sky Objects, An Annotated Catalogue, Springer New York, p. 92, ISBN 9781441994196, https://books.google.com/books?id=gc9oXfN3xYAC&pg=PA92. 
  11. Esipov, V. F. et al. (October 1991), "UBVR Photometry and Rotation of Late Type Galaxies - NGC959 NGC1156 NGC1160 NGC6643 and NGC7292", Soviet Astronomy 35 (5): 452, Bibcode1991SvA....35..452E. 

External links