NGC 959

NGC 959 is a spiral galaxy in the northern constellation of Triangulum.^[10] It was discovered on 9 November 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]

NGC 959
NGC 959 imaged by the Hubble Space Telescope
Observation data (J2000 epoch)
Constellation	Triangulum
Right ascension	02h 32m 23.923s[1]
Declination	+35° 29′ 40.46″[1]
Heliocentric radial velocity	596 km/s[2]
Distance	36 Mly (11.0 Mpc)[2][3]
Group or cluster	NGC 1023 Group[4]
Apparent magnitude (V)	12.38±0.14[3]
Apparent magnitude (B)	12.95±0.14[3]
Characteristics
Type	Sdm:[3] or SBcd[5]
Mass	6.3×108[6] (stellar) M☉
Size	21.8 kly (6.69 kpc)[7]
Apparent size (V)	2′.3 × 1′.4[3] (D25)
Other designations
IRAS 02293+3516, NGC 959, UGC 2002, LEDA 9665, MCG +06-06-051, PGC 9665[8][9]

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 plane of the sky,^[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. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
2. 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.
3. Gil de Paz, Armando; et al. (December 2007), "The GALEX Ultraviolet Atlas of Nearby Galaxies", The Astrophysical Journal Supplement Series, 173 (2): 185–255, arXiv:astro-ph/0606440, Bibcode:2007ApJS..173..185G, doi:10.1086/516636, S2CID 119085482.
4. 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, arXiv:0906.2540, Bibcode:2009MNRAS.398..722T, doi:10.1111/j.1365-2966.2009.15189.x, S2CID 18442520.
5. 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, arXiv:1004.3575, Bibcode:2010AJ....139.2557T, doi:10.1088/0004-6256/139/6/2557, S2CID 119274723.
6. 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, arXiv:1911.05836, Bibcode:2019ApJ...887...94R, doi:10.3847/1538-4357/ab5305, S2CID 208006358, 94.
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, Bibcode:2017ApJ...843...37T, doi:10.3847/1538-4357/aa76eb, S2CID 23645373, 37.
8. "NGC 959". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2022-01-18.{{cite web}}: CS1 maint: postscript (link)
9. Seligman, Courtney, "NGC Objects: NGC 950 - 999", Celestial Atlas, retrieved 2022-01-18.
10. Aranda, Ted (2011), 3,000 Deep-Sky Objects, An Annotated Catalogue, Springer New York, p. 92, ISBN 9781441994196.
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, Bibcode:1991SvA....35..452E.

External links

• "Results for object NGC 0959 (NGC 959)". NASA/IPAC Extragalactic Database (NED). California Institute of Technology. Retrieved 2022-01-19.