NGC 6541

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NGC 6541
Caldwell 78 (50291821361).jpg
NGC 6541, imaged by the Hubble Space Telescope
Observation data (J2000 epoch)
Class III [1]
Constellation Corona Australis
Right ascension 18h 08m 02.36s [2]
Declination –43° 42 53.6 [2]
Distance 22.8  kly (7.0  kpc) [3]
Apparent magnitude (V)6.3
Apparent dimensions (V)15
Physical characteristics
Absolute magnitude −8.52
Mass5.72×105 [4]   M
Metallicity  = –1.53 [5] dex
Estimated age12.93  Gyr [5]
Other designations Caldwell 78
See also: Globular cluster, List of globular clusters

NGC 6541 (also known as Caldwell 78) is a globular cluster in the southern constellation of Corona Australis. It is estimated to be around 14 billion years old. [6]

The globular cluster was discovered by Niccolò Cacciatore at the Palermo Astronomical Observatory, Sicily, on March 19, 1826. It was independently found by James Dunlop on July 3, 1826.

The cluster is relatively small, having just 94 blue straggler stars. [7]

NGC 6541 NGC 6541.jpg
NGC 6541

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References

  1. Shapley, Harlow; Sawyer, Helen B. (August 1927), "A Classification of Globular Clusters", Harvard College Observatory Bulletin, 849 (849): 11–14, Bibcode:1927BHarO.849...11S.
  2. 1 2 Goldsbury, Ryan; et al. (December 2010), "The ACS Survey of Galactic Globular Clusters. X. New Determinations of Centers for 65 Clusters", The Astronomical Journal, 140 (6): 1830–1837, arXiv: 1008.2755 , Bibcode:2010AJ....140.1830G, doi:10.1088/0004-6256/140/6/1830, S2CID   119183070.
  3. Paust, Nathaniel E. Q.; et al. (February 2010), "The ACS Survey of Galactic Globular Clusters. VIII. Effects of Environment on Globular Cluster Global Mass Functions", The Astronomical Journal, 139 (2): 476–491, Bibcode:2010AJ....139..476P, doi:10.1088/0004-6256/139/2/476, hdl: 2152/34371 , S2CID   120965440.
  4. 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.
  5. 1 2 Forbes, Duncan A.; Bridges, Terry (May 2010), "Accreted versus in situ Milky Way globular clusters", Monthly Notices of the Royal Astronomical Society , 404 (3): 1203–1214, arXiv: 1001.4289 , Bibcode:2010MNRAS.404.1203F, doi:10.1111/j.1365-2966.2010.16373.x, S2CID   51825384.
  6. O'Meara, Stephen James (2011). Deep-Sky Companions: The Secret Deep. Cambridge, United Kingdom: Cambridge University Press. p. 322. ISBN   978-0521198769.
  7. Raso, S.; Ferraro, F. R.; Dalessandro, E.; Lanzoni, B.; Nardiello, D.; Bellini, A.; Vesperini, E. (2017), "The "UV-route" to Search for Blue Straggler Stars in Globular Clusters: First Results from theHSTUV Legacy Survey", The Astrophysical Journal, 839 (1): 64, arXiv: 1704.01453 , Bibcode:2017ApJ...839...64R, doi: 10.3847/1538-4357/aa6891 , S2CID   118939669