NGC 6522

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NGC 6522
NGC 6522 ACS 435 658 Wiki.jpg
Observation data (J2000 epoch)
Constellation Sagittarius
Right ascension 18h 03m 34.1s [1]
Declination −30° 02 2.3 [1]
Distance 25.1  kly (7.7  kpc) [2]
Apparent magnitude (V)8.3 [3]
Apparent dimensions (V)16.4' [3]
Physical characteristics
Mass3.00×105 [2]   M
Metallicity  = –1.34 [2] dex
Estimated age12.0  Gyr [4]
Other designationsGCl 82, C 1800-300 [1]
See also: Globular cluster, List of globular clusters

NGC 6522 is a globular cluster in the constellation Sagittarius. It is apparent magnitude 8.3, and diameter 16.4 arc minutes, and class VI with stars 16th magnitude and dimmer. It was discovered by William Herschel on June 24, 1784. It is centered in a region of the sky known as Baade's Window. [1] [3]

Contents

NGC 6522 is possibly the oldest star cluster in the Milky Way, [5] with an age of more than 12 billion years. [6]

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<span class="mw-page-title-main">NGC 6496</span> Globular cluster in the constellation Scorpius

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<span class="mw-page-title-main">NGC 5286</span> Globular cluster in the constellation Centaurus

NGC 5286 is a globular cluster of stars located some 35,900 light years away in the constellation Centaurus. At this distance, the light from the cluster has undergone reddening from interstellar gas and dust equal to E(B – V) = 0.24 magnitude in the UBV photometric system. The cluster lies 4 arc-minutes north of the naked-eye star M Centauri. It was discovered by Scottish astronomer James Dunlop, active in Australia, and listed in his 1827 catalog.

References

  1. 1 2 3 4 "SIMBAD Astronomical Database". Results for NGC 6522. Retrieved 2011-03-13.
  2. 1 2 3 Boyles, J.; et al. (November 2011), "Young Radio Pulsars in Galactic Globular Clusters", The Astrophysical Journal, 742 (1): 51, arXiv: 1108.4402 , Bibcode:2011ApJ...742...51B, doi:10.1088/0004-637X/742/1/51, S2CID   118649860.
  3. 1 2 3 "NGC 6522" . Retrieved 2020-09-23.
  4. Koleva, M.; et al. (April 2008), "Spectroscopic ages and metallicities of stellar populations: validation of full spectrum fitting", Monthly Notices of the Royal Astronomical Society , 385 (4): 1998–2010, arXiv: 0801.0871 , Bibcode:2008MNRAS.385.1998K, doi:10.1111/j.1365-2966.2008.12908.x, S2CID   17571531
  5. "VLT-FLAMES Analysis of 8 giants in the Bulge Metal-poor Globular Cluster NGC 6522: Oldest Cluster in the Galaxy?" by B. Barbuy et al., 2009
  6. "The universe's first stars were whirling dervishes", New Scientist by David Shiga, 30 April 2011, p. 20. "Imprints of fast-rotating massive stars in the Galactic Bulge" by Cristina Chiappini et al., Nature 472, pp. 454–457 (28 April 2011).