NGC 6250 is a open cluster of stars in the southern constellation of Ara, near the border with Scorpius.[5] It was discovered by English astronomer John Herschel on July 1, 1834.[6] This cluster has an apparent visual magnitude of 5.9 and spans an angular diameter of 18′,[2] with the brightest member being of magnitude 7.6. About 15 members are visible with binoculars or a small telescope.[7] NGC 6250 is located at a distance of 2,820 ly (865 pc) from the Sun,[1] and is approaching with a mean radial velocity of −10±6 km/s.[8]
| NGC 6250 | |
|---|---|
 | |
| Observation data (J2000 epoch) | |
| Right ascension | 16h 57m 58.(0)s[1] |
| Declination | −45° 56′ 3(6)″[1] |
| Distance | 2,820 ly (865 pc)[1] |
| Apparent magnitude (V) | 5.9[2] |
| Apparent dimensions (V) | 18′[2] |
| Physical characteristics | |
| Estimated age | 14 Ma[3] |
| Other designations | NGC 6250, Cr 320, C 1654-457, ESO 277-SC20, OCL 991, VDBH 206.[4] |
| Associations | |
| Constellation | Ara |
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).[9] This is a young cluster with an estimated age of 14 million years.[3] Seven cluster members are B-type stars,[10] and three are illuminating reflection nebulae.[11] Two magnetic chemically peculiar stars (CP2) and two candidate Lambda Boötis stars have been identified as members.[9] The metallicity of the cluster members is consistent with the Sun.[8]
References
edit- ^ a b c d 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.
- ^ a b c 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.
- ^ a b 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.
- ^ "NGC 6250 -- Open (galactic) Cluster", SIMBAD, Centre de Données astronomiques de Strasbourg, retrieved 2015-09-13.
- ^ Harrington, Philip S. (1990), Touring the Universe Through Binoculars: A Complete Astronomer's Guidebook, Turner Publishing Company, pp. 58–59, ISBN 9781620459492.
- ^ Seligman, Courtney, "NGC Objects: NGC 6250 - 6299", Celesial Atlas, retrieved 2024-05-22.
- ^ Simpson, Phil (2012), Guidebook to the Constellations: Telescopic Sights, Tales, and Myths, Springer New York, p. 272, ISBN 9781441969415.
- ^ a b 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.
- ^ a b 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.
- ^ 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.
- ^ 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.
External links
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Media related to NGC 6250 at Wikimedia Commons- Image NGC 6250
- http://seds.org/
