Astronomy:NGC 6250
| NGC 6250 | |
|---|---|
 | |
| Observation data (J2000 epoch) | |
| Constellation | Ara |
| 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, C 1654-457, ESO 277-SC20, OCL 991, VDBH 206.[4] |
NGC 6250 is an 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]
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
- ↑ 1.0 1.1 1.2 1.3 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, doi:10.1051/0004-6361:20011021, Bibcode: 2001A&A...376..441D.
- ↑ 2.0 2.1 2.2 Inglis, Mike (2013), Observer's Guide to Star Clusters, The Patrick Moore Practical Astronomy Series, Springer Science & Business Media, p. 27, ISBN 978-1461475675, Bibcode: 2013ogsc.book.....I, https://books.google.com/books?id=ewHABAAAQBAJ&pg=PA27.
- ↑ 3.0 3.1 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, doi:10.1111/j.1365-2966.2008.13917.x, Bibcode: 2008MNRAS.391..447F.
- ↑ "NGC 6250 -- Open (galactic) Cluster", SIMBAD (Centre de Données astronomiques de Strasbourg), http://simbad.u-strasbg.fr/simbad/sim-id?Ident=NGC+6250, 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, https://books.google.com/books?id=So3uEAAAQBAJ&pg=PT59.
- ↑ Seligman, Courtney, "NGC Objects: NGC 6250 - 6299", Celesial Atlas, https://cseligman.com/text/atlas/ngc62a.htm#6250, retrieved 2024-05-22.
- ↑ Simpson, Phil (2012), Guidebook to the Constellations: Telescopic Sights, Tales, and Myths, Springer New York, p. 272, ISBN 9781441969415, https://books.google.com/books?id=7gde2t9ta4QC&pg=PA272.
- ↑ 8.0 8.1 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, doi:10.1093/mnras/stw3052, Bibcode: 2017MNRAS.466..613M.
- ↑ 9.0 9.1 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, doi:10.1051/aas:2000294, Bibcode: 2000A&AS..147...99B.
- ↑ 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, doi:10.1086/432757, Bibcode: 2005ApJS..161..118M.
- ↑ 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, doi:10.1086/112144, Bibcode: 1977AJ.....82..902H.
External links
 |  |
