Blanco 1
Blanco 1 (ζ Sculptoris cluster) is a nearby open cluster of stars located around 850 light years away from the Sun in the southern constellation of Sculptor near the star ζ Sculptoris. It was discovered by Puerto Rican astronomer Víctor Manuel Blanco in 1949,[1] who noticed an unusually high proportion of A-type stars in an area spanning 1.5°.[2] This cluster is relatively young, with an age of about 100–150 million years. It is positioned at a high galactic latitude of b = –79.3° and is located some 780 ly (240 pc) below the galactic plane.
Blanco 1 | |
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Observation data (J2000 epoch) | |
Constellation | Sculptor |
Right ascension | 00h 04m 24s[1] |
Declination | –29° 56.4′[1] |
Distance | 850+160 −130 ly (260+50 −40 pc)[1] |
Physical characteristics | |
Estimated age | 100–150[1] Myr |
Blanco 1 contains approximately 300 stars, around 170 of these being brighter than magnitude +12,[3] the brightest of which is HD 225187, a 7th-magnitude B8V star. It has a cross-sectional magnitudal density of about 30 per square parsec: less than half that of the Pleiades cluster. Of the confirmed members, eight have been found to radiate an excess of infrared energy, indicating that they host orbiting debris disks.[4] Roughly half the stars in the cluster are members of binary star systems; six of the member stars are confirmed spectroscopic binaries.[5] There are also some 30–40 brown dwarf members.[1]
References
- Moraux, E.; et al. (August 2007), "The lower mass function of the young open cluster Blanco 1: from 30 MJup to 3 M⊙", Astronomy and Astrophysics, 471 (2): 499–513, arXiv:0706.2102, Bibcode:2007A&A...471..499M, doi:10.1051/0004-6361:20066308.
- Blanco, Victor M. (August 1949), "A New Galactic Star Cluster in Sculptor", Publications of the Astronomical Society of the Pacific, 61 (361): 183, Bibcode:1949PASP...61..183B, doi:10.1086/126171.
- Bagnall, Philip M. (2012), The Star Atlas Companion: What You Need to Know about the Constellations, Springer, p. 409, ISBN 146140830X.
- Stauffer, John R.; et al. (August 1949), "Debris Disks of Members of the Blanco 1 Open Cluster", The Astrophysical Journal, 719 (2): 1859–1871, arXiv:1007.0239, Bibcode:2010ApJ...719.1859S, doi:10.1088/0004-637X/719/2/1859.
- González, J. F.; Levato, H. (November 2009), "Spectroscopic study of the open cluster Blanco 1", Astronomy and Astrophysics, 507 (1): 541–547, Bibcode:2009A&A...507..541G, doi:10.1051/0004-6361/200912772.