IC 4499

IC 4499 is a loose globular cluster in the constellation Apus. It is located in the medium-far galactic halo.[4] Its apparent magnitude is 9.76,[1] and was thought to unusual because it appears to be 3-4 billion years younger than most other globular clusters in the Milky Way, as determined by metallicity measurements in 1995.[4] However, this was contradicted in 2011 by results that yielded a much older age of 12 billion years.[5]

IC 4499
IC 4499, as seen through the Hubble Space Telescope
Credit: NASA/ESA
Observation data (J2000 epoch)
ClassXI[1]
ConstellationApus
Right ascension 15h 00m 18.57s[2]
Declination−82° 12′ 49.6″[2]
Distance50,000 ly (15,000 pc)[1]
Apparent magnitude (V)9.76[3]
Apparent dimensions (V)7.6′ × 7.6′[1]
Physical characteristics
Metallicity = -1.53[3] dex
Other designationsGCl 30[2]

References
  1. Frommert, Hartmut. "IC 4499". Students for the Exploration and Development of Space. Retrieved 22 April 2012.
  2. "IC 4499". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 20 February 2017.
  3. William E. Harris. "Catalog of Parameters for Milky Way Globular Clusters". Retrieved 3 February 2017.
  4. Ferraro, I.; Ferraro, F.R.; Pecci, F. Fusi; Corsi, C.E.; Buonanno, R. (August 1995). "Young globular clusters in the Milky Way: IC 4499". Monthly Notices of the Royal Astronomical Society. SAO/NASA ADS Astronomy Abstract Service. 275 (4): 1057–1076. Bibcode:1995MNRAS.275.1057F. doi:10.1093/mnras/275.4.1057.
  5. Walker, A. R.; et al. (July 2011), "Constraints on the formation of the globular cluster IC 4499 from multiwavelength photometry", Monthly Notices of the Royal Astronomical Society, 415 (1): 643–654, arXiv:1103.4144, Bibcode:2011MNRAS.415..643W, doi:10.1111/j.1365-2966.2011.18736.x.


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