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 be 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
Observation data (J2000 epoch)
Class	XI[1]
Constellation	Apus
Right ascension	15h 00m 18.57s[2]
Declination	−82° 12′ 49.6″[2]
Distance	50,000 ly (15,000 pc)[1]
Apparent magnitude (V)	9.76[3]
Apparent dimensions (V)	7.6′ × 7.6′[1]
Physical characteristics
Metallicity	${\displaystyle {\begin{smallmatrix}\left[{\ce {Fe}}/{\ce {H}}\right]\end{smallmatrix}}}$ = -1.53[3] dex
Other designations	GCl 30, Melotte 129[2]
See also: Globular cluster, List of globular clusters

As typical for very old globular clusters, IC 4499 contains two generations of stars.[6]

References

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