NGC 5694

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NGC 5694
NGC 5694.jpg
The core of NGC 5694 imaged by the Hubble Space Telescope
Observation data (J2000 epoch)
Class VII [1]
Constellation Hydra
Right ascension 14h 39m 36.5s [2]
Declination −26° 32 18.0 [2]
Distance 114,100ly [1]
Apparent magnitude (V)10.2 [1]
Apparent dimensions (V)3.6 [1]
Physical characteristics
Metallicity  = –1.74 [3] dex
Estimated age13.44  Gyr [3]
Other designations Caldwell  66
See also: Globular cluster, List of globular clusters

NGC 5694 (also known as Caldwell 66) is a globular cluster in the constellation Hydra. It was discovered in 1784 by William Herschel.

Contents

Characteristics

This globular cluster is located at a distance of 114,000 light-years (35,000 pc) from the Sun and 96,000 light-years (29,000 pc) from the Galactic Center [4] and is one of the oldest known globular clusters in the Milky Way Galaxy, forming nearly 12 billion years ago. [5]

Its chemical composition is highly peculiar, being highly (to nearly solar levels) enriched in alpha elements, suggesting an extragalactic origin before being captured by the Milky Way. [6]

See also

Related Research Articles

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References

  1. 1 2 3 4 "Results for NGC 5694". SEDS NGC Catalog Online. Retrieved 2010-12-07.
  2. 1 2 "NGC 5694". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2010-12-07.
  3. 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.
  4. Harris, W.E. (1996). "A Catalog of Parameters for Globular Clusters in the Milky Way". The Astronomical Journal. 112: 1487. Bibcode:1996AJ....112.1487H. doi:10.1086/118116.
  5. "NGC/IC Project". Results for NGC 5694. Archived from the original on 2012-05-20. Retrieved 2010-12-07.
  6. Mucciarelli, A.; Bellazzini, M.; Catelan, M.; Dalessandro, E.; Amigo, P.; Correnti, M.; Cortés, C.; d'Orazi, V. (2013), "NGC 5694: Another foster son of the Galactic halo★", Monthly Notices of the Royal Astronomical Society, 435 (4): 3667–3680, arXiv: 1308.6653 , doi:10.1093/mnras/stt1558