Astronomy:NGC 6584

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Short description: Globular cluster in the constellation Telescopium
NGC 6584
NGC 6584 as observed by the Hubble Space Telescope.
Observation data (J2000 epoch)
ConstellationTelescopium
Right ascension 18h 18m 37.60s[1]
Declination–52° 12′ 56.8″[1]
Distance45000[2]
Apparent dimensions (V)7.9'
Physical characteristics
Metallicity[math]\displaystyle{ \begin{smallmatrix}\left[\ce{Fe}/\ce{H}\right]\end{smallmatrix} }[/math] = −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]

References

  1. 1.0 1.1 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, doi:10.1088/0004-6256/140/6/1830, Bibcode2010AJ....140.1830G. 
  2. 2.0 2.1 Streicher, Magda (August 2009). "A Spyglass Telescope". Deepsky Delights 68: 168. Bibcode2009MNSSA..68..168S. http://mnassa.saao.ac.za/sections/deepsky/delights/2009_aug_deepsky_delights.pdf. Retrieved 29 September 2012. 
  3. 3.0 3.1 3.2 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. Bibcode2012JSARA...6...63T. 
  5. "Physical Parameters of Galactic Globular Clusters" by S. Djorgovski

External links