NGC 6250

NGC 6250
Observation data (J2000 epoch)
Right ascension16h 57m 58.(0)s
Declination−45° 56′ 3(6)″
Distance2,820 ly (865 pc)
Apparent magnitude (V)5.9
Apparent dimensions (V)10′
Physical characteristics
Estimated age14 Ma
Other designationsNGC 6250, Cr 320, C 1654-457, ESO 277-SC20, OCL 991, VDBH 206.
Associations
ConstellationAra
See also: Open cluster, List of open clusters

NGC 6250 is an open cluster of stars in the southern constellation of Ara, near the border with Scorpius. It was discovered by English astronomer John Herschel on July 1, 1834. This cluster has an apparent visual magnitude of 5.9 and spans an angular diameter of 10′, with the brightest member being of magnitude 7.6. About 15 members are visible with binoculars or a small telescope. NGC 6250 is located at a distance of 2,820 ly (865 pc) from the Sun, and is approaching with a mean radial velocity of −10±6 km/s.

The Trumpler classification of NGC 6250 is II 3 r, indicating a rich cluster of stars (r) with a slightly disparate grouping (II) and a large brightness range (3). This is a young cluster with an estimated age of 14 million years. Seven cluster members are B-type stars, and three are illuminating reflection nebulae. Two magnetic chemically peculiar stars (CP2) and two candidate Lambda Boötis stars have been identified as members. The metallicity of the cluster members is consistent with the Sun.

References

  1. 1 2 3 4 Dias, W. S.; et al. (September 2001), "Proper motions of open clusters within 1 kpc based on the TYCHO2 Catalogue", Astronomy and Astrophysics, 376 (2): 441–447, Bibcode:2001A&A...376..441D, doi:10.1051/0004-6361:20011021.
  2. 1 2 3 Inglis, Mike (2013), Observer's Guide to Star Clusters, The Patrick Moore Practical Astronomy Series, Springer Science & Business Media, p. 27, Bibcode:2013ogsc.book.....I, ISBN 978-1461475675.
  3. 1 2 Feinstein, Carlos; et al. (November 2008), "Optical polarization study in the open cluster NGC 6250", Monthly Notices of the Royal Astronomical Society, 391 (1): 447–456, Bibcode:2008MNRAS.391..447F, doi:10.1111/j.1365-2966.2008.13917.x, hdl:11336/44115.
  4. ↑ "NGC 6250 -- Open (galactic) Cluster", SIMBAD, Centre de Données astronomiques de Strasbourg, retrieved 2015-09-13.
  5. ↑ Harrington, Philip S. (1990), Touring the Universe Through Binoculars: A Complete Astronomer's Guidebook, Turner Publishing Company, pp. 58–59, ISBN 9781620459492.
  6. ↑ Seligman, Courtney, "NGC Objects: NGC 6250 - 6299", Celesial Atlas, retrieved 2024-05-22.
  7. ↑ Simpson, Phil (2012), Guidebook to the Constellations: Telescopic Sights, Tales, and Myths, Springer New York, p. 272, ISBN 9781441969415.
  8. 1 2 Martin, A. J.; et al. (April 2017), "A spectroscopic study of the open cluster NGC 6250", Monthly Notices of the Royal Astronomical Society, 466 (1): 613–627, arXiv:1612.05739, Bibcode:2017MNRAS.466..613M, doi:10.1093/mnras/stw3052.
  9. 1 2 Bayer, C.; et al. (November 2000), "CCD photometric search for peculiar stars in open clusters. I. NGC 2169, Melotte 105 and NGC 6250", Astronomy and Astrophysics Supplement, 147: 99–109, Bibcode:2000A&AS..147...99B, doi:10.1051/aas:2000294.
  10. ↑ McSwain, M. Virginia; Gies, Douglas R. (November 2005), "The Evolutionary Status of Be Stars: Results from a Photometric Study of Southern Open Clusters", The Astrophysical Journal Supplement Series, 161 (1): 118–146, arXiv:astro-ph/0505032, Bibcode:2005ApJS..161..118M, doi:10.1086/432757.
  11. ↑ Herbst, W. (November 1977), "Extinction law in dust clouds and the young southern cluster NGC 6250: further evidence for high values of R", Astronomical Journal, 82: 902–907, Bibcode:1977AJ.....82..902H, doi:10.1086/112144.