NGC 6584

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NGC 6584
NGC 6584.jpg
Observation data (J2000 epoch)
Constellation Telescopium
Right ascension 18h 18m 37.60s [1]
Declination –52° 12 56.8 [1]
Distance 45000 [2]
Apparent dimensions (V)7.9'
Physical characteristics
Metallicity  = −1.53±0.08 [3] dex
Estimated age11.6±1.7 Gyr [3]
See also: Globular cluster, List of globular clusters

NGC 6584 is a globular cluster in the constellation Telescopium that lies near Theta Arae and is 45000 light-years distant. [2] It is an Oosterhoff type I cluster, and contains at least 69 variable stars, most of which are RR Lyrae variables: 46 stars were identified as RRab variables; 15 as RRc variables, 1 RRe variable, 4 eclipsing binaries and 3 long period variables. [4] NGC 6584 is about 4 kpc from the Galactic center and about 2.7 kpc from the Galactic plane. [5]

As is typical for metal-poor globular clusters, NGC 6584 has an enhanced concentration of alpha elements relative to iron. [3]

Related Research Articles

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<span class="mw-page-title-main">NGC 6352</span> Globular cluster in the constellation Ara

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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 6441</span> Globular cluster in Scorpius

NGC 6441 is a globular cluster in the southern constellation of Scorpius. It was discovered by the Scottish astronomer James Dunlop on May 13, 1826, who described it as "a small, well-defined rather bright nebula, about 20″ in diameter". The cluster is located 5 arc minutes east-northeast of the star G Scorpii, and is some 43,000 light-years from the Sun.

<span class="mw-page-title-main">NGC 5053</span> Globular cluster in the constellation Coma Berenices

NGC 5053 is the New General Catalogue designation for a globular cluster in the northern constellation of Coma Berenices. It was discovered by German-British astronomer William Herschel on March 14, 1784 and cataloged as VI-7. In his abbreviated notation, he described it as, "an extremely faint cluster of extremely small stars with resolvable nebula 8 or 10′ diameter, verified by a power of 240, beyond doubt". Danish-Irish astronomer John Louis Emil Dreyer reported in 1888 that the cluster appeared, "very faint, pretty large, irregular round shape, growing very gradually brighter at the middle".

References

  1. 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.
  2. 1 2 Streicher, Magda (August 2009). "A Spyglass Telescope" (PDF). Deepsky Delights. 68: 168. Bibcode:2009MNSSA..68..168S . Retrieved 29 September 2012.[ permanent dead link ]
  3. 1 2 3 High-resolution Spectroscopic Abundances of Red Giant Branch Stars in NGC 6584 and NGC 7099
  4. Toddy, Joseph M.; Johnson, Elliott W.; Darragh, Andrew N.; Murphy, Brian W. (2012). "New Variable Stars in the Globular Cluster NGC 6584". Journal of the Southeastern Association for Research in Astronomy. 6: 63–71. arXiv: 1205.1034 . Bibcode:2012JSARA...6...63T.
  5. "Physical Parameters of Galactic Globular Clusters" by S. Djorgovski