Messier 62

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Globular cluster
Messier 62
Center of Messier 62 imaged with the Hubble Space Telescope, angle of view 2.7 '× 2.8'
Center of Messier 62 imaged with the Hubble Space Telescope , angle of view 2.7 '× 2.8'
AladinLite
Constellation Snake bearer
Position
equinox :  J2000.0 , epoch : J2000.0
Right ascension 17 h 1 m 12.6 s
declination −30 ° 06 ′ 45 ″
Appearance
Concentration class IV
Brightness  (visual) 6.4 mag
Brightness  (B-band) 8.55 likes
Angular expansion 14.1 '
Physical data
Integrated spectral type F9
Redshift −0.000227 ± 0.000011
Radial velocity (−68 ± 3) km / s
distance 22.5  kLj
(6.9  kpc ) 
history
discovery Charles Messier
Discovery date June 7, 1771
Catalog names
 M  62 •  NGC  6266 • C 1658-300 •  GCl  51 •  ESO  453-SC014 •

Messier 62 (also known as NGC 6266 ) is a 6.4  mag bright globular cluster with an angular extent of 14.1 ′ in the constellation of the Serpent Bearer . It is about 22,200 light years from Earth and 5,500 light years from the Galactic Center , and one of the ten most massive and brightest globular clusters in the Milky Way .

The globular cluster consists of around 500,000 stars and has a total mass of 1.22 million solar masses . These can be separated into two star generations: 79% of the main sequence stars come from the first generation and 21% from the second. The second generation has a higher proportion of helium, carbon, magnesium, aluminum and sodium, elements that were created by nuclear fusion in the first generation .

In the star cluster were 245 variable stars , of which 209 are RR Lyrae stars , 4 are Type II Cepheids , 25 are long period variables , and one is an eclipsing binary . The cluster may prove to be the galaxy's richest in terms of RR Lyrae variables. The globular cluster contains 6 binary millisecond pulsars , one of which (COM6266B) shows an eclipsing behavior, caused by gases escaping from its companion. There are a number of X-ray sources in the star cluster , 50 of which are within the half-mass radius. 47 Blue Straggler candidates were identified, the concentration of which increases towards the star cluster core.

M62 is difficult to observe in Central Europe because of its southern position.

Individual evidence

  1. ↑ a b c d SIMBAD query
  2. ↑ NASA / IPAC Extragalactic Database
  3. ↑ SEDS : NGC 6266
  4. ↑ M62 at SEDS
  5. ↑ Seligman
  6. ↑ a b J. Boyles, DR Lorimer, PJ Turk, R. Mnatsakanov, RS Lynch, SM Ransom, PC Freire, K. Belczynski: Young Radio Pulsars in Galactic Globular Clusters . In: The Astrophysical Journal . 742, No. 1, November 2011, p. 51. arxiv : 1108.4402 . bibcode : 2011ApJ ... 742 ... 51B . doi : 10.1088 / 0004-637X / 742/1/51 .
  7. ↑ M. Di Criscienzo, F. Caputo, M. Marconi, I. Musella: RR Lyrae-based calibration of the Globular Cluster Luminosity Function . In: Monthly Notices of the Royal Astronomical Society . 365, No. 4, February 2006, pp. 1357-1366. arxiv : astro-ph / 0511128 . bibcode : 2006MNRAS.365.1357D . doi : 10.1111 / j.1365-2966.2005.09819.x .
  8. ↑ a b A. P. Milone: Helium and multiple populations in the massive globular cluster NGC 6266 (M 62) . In: Monthly Notices of the Royal Astronomical Society . 446, No. 2, January 2015, pp. 1672–1684. arxiv : 1409.7230 . bibcode : 2015MNRAS.446.1672M . doi : 10.1093 / mnras / stu2198 .
  9. ^ R. Contreras, M. Catelan, HA Smith, BJ Pritzl, J. Borissova, CA Kuehn: Time-series Photometry of Globular Clusters: M62 (NGC 6266), the Most RR Lyrae-rich Globular Cluster in the Galaxy? . In: The Astronomical Journal . 140, No. 6, December 2010, pp. 1766-1786. arxiv : 1009.4206 . bibcode : 2010AJ .... 140.1766C . doi : 10.1088 / 0004-6256 / 140/6/1766 .
  10. Jump up ↑ G. Cocozza, FR Ferraro, A. Possenti, G. Beccari, B. Lanzoni, S. Ransom, RT Rood, N. D'Amico: A Puzzling Millisecond Pulsar Companion in NGC 6266 . In: The Astrophysical Journal Letters . 679, No. 2, June 2008, p. L105. arxiv : 0804.3574 . bibcode : 2008ApJ ... 679L.105C . doi : 10.1086 / 589557 .
  11. ^ A b G. Beccari, FR Ferraro, A. Possenti, E. Valenti, L. Origlia, RT Rood: The Dynamical State and Blue Straggler Population of the Globular Cluster NGC 6266 (M62) . In: The Astronomical Journal . 131, No. 5, May 2006, pp. 2551-2560. arxiv : astro-ph / 0601187 . bibcode : 2006AJ .... 131.2551B . doi : 10.1086 / 500643 .