NGC 458

NGC 458
NGC 458 as seen by DECam
Observation data (J2000 epoch)
Right ascension01h 14m 53.36s[1]
Declination−71° 32′ 58.7″[1]
Apparent magnitude (V)11.73[2]
Apparent dimensions (V)2.6′ × 2.3′[1]
Physical characteristics
Mass2.6×104[2] M☉
Estimated age0.14±0.03 Gyr[2]
Other designationsKron 69, Lindsay 96, ESO 51-26, RZ2005 197.[1]
Associations
ConstellationTucana
See also: Open cluster, List of open clusters

NGC 458 is an open cluster located in the constellation Tucana. It was discovered on September 6, 1826, by James Dunlop. It was also observed by John Herschel and DeLisle Stewart. It was described by Dreyer as "pretty faint, large, round, very gradually brighter middle". It was also noted in the second Index Catalogue that it was "probably a cluster, extremely small, close, no nebulosity seen by D.S. (DeLisle Stewart)."[3] At an aperture of 31 arcseconds, its apparent V-band magnitude is 11.73, but at this wavelength, it has 0.12 magnitudes of interstellar extinction.[2]

NGC 458 is quite young, at about 140 million years old. Its estimated mass is 2.6×104 M☉, and its total luminosity is 1.24×105 L☉, leading to a mass-to-luminosity ratio of 0.21 M☉/L☉. However, the dynamical mass may be inaccurate due to the small stellar sample used in the analysis.[2] All else equal, older star clusters have higher mass-to-luminosity ratios; that is, they have lower luminosities for the same mass.[2]

  1. ^ a b c d "NGC 458". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 21 May 2017.
  2. ^ a b c d e f Song, Ying-Yi; Mateo, Mario; Bailey, John I.; Walker, Matthew G.; Roederer, Ian U.; Olszewski, Edward W.; Reiter, Megan; Kremin, Anthony (2021). "Dynamical masses and mass-to-light ratios of resolved massive star clusters – II. Results for 26 star clusters in the Magellanic Clouds". Monthly Notices of the Royal Astronomical Society. 504 (3): 4160–4191. arXiv:2104.06882. doi:10.1093/mnras/stab1065.
  3. ^ "New General Catalog Objects: NGC 450 - 499". Cseligman. Retrieved May 21, 2017.