Star in the constellation Cetus
Xi2 Ceti , Latinized from ξ2 Ceti, is a star located in the equatorial constellation of Cetus . It is visible to the naked eye with an apparent visual magnitude of +4.3.[ 2] This star is located at a distance of approximately 197 light years from the Sun based on parallax , and is drifting further away with a radial velocity of 12 km/s.[ 6] It made its closest approach some 2.7 million years ago at a distance of around 128 light-years.[ 5]
Xi2 Ceti is a spectrophotometric standard star.[ 2] It displays a stellar classification of B9.5III,[ 3] which suggests it has exhausted its core hydrogen, evolved away from the main sequence , and expanded to become a giant star , although still only 127 million years old.[ 7] It has 2.45[ 7] times the mass and 2.6[ 8] times the radius of the Sun.
In Chinese , 天囷 (Tiān Qūn ), meaning Circular Celestial Granary , refers to an asterism consisting of α Ceti , κ1 Ceti , λ Ceti , μ Ceti , ξ1 Ceti , ξ2 Ceti, ν Ceti , γ Ceti , δ Ceti , 75 Ceti , 70 Ceti , 63 Ceti and 66 Ceti . Consequently, the Chinese name for Xi2 Ceti itself is "the Sixth Star of Circular Celestial Granary", Tiān Qūn Liù .[ 10]
References
^ a b c d e Brown, A. G. A. ; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties" . Astronomy & Astrophysics . 616 . A1. arXiv :1804.09365 . Bibcode :2018A&A...616A...1G . doi :10.1051/0004-6361/201833051 . Gaia DR2 record for this source at VizieR .
^ a b c Bessell, Michael S. (1999). "Spectrophotometry: Revised Standards and Techniques" . Publications of the Astronomical Society of the Pacific . 111 (765): 1426– 1433. Bibcode :1999PASP..111.1426B . doi :10.1086/316454 .
^ a b Cowley, A.; et al. (April 1969). "A study of the bright A stars. I. A catalogue of spectral classifications". Astronomical Journal . 74 : 375– 406. Bibcode :1969AJ.....74..375C . doi :10.1086/110819 .
^ Gray, R. O.; Garrison, R. F. (1987). "The Early A-Type Stars: Refined MK Classification, Confrontation with Stroemgren Photometry, and the Effects of Rotation" . The Astrophysical Journal Supplement Series . 65 : 581. Bibcode :1987ApJS...65..581G . doi :10.1086/191237 .
^ a b c d e f Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters . 38 (5): 331. arXiv :1108.4971 . Bibcode :2012AstL...38..331A . doi :10.1134/S1063773712050015 . S2CID 119257644 .
^ a b Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system". Astronomy Letters . 32 (11): 759– 771. arXiv :1606.08053 . Bibcode :2006AstL...32..759G . doi :10.1134/S1063773706110065 . S2CID 119231169 .
^ a b c d e David, Trevor J.; Hillenbrand, Lynne A. (2015). "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal . 804 (2): 146. arXiv :1501.03154 . Bibcode :2015ApJ...804..146D . doi :10.1088/0004-637X/804/2/146 . S2CID 33401607 .
^ a b c Gordon, Kathryn D.; et al. (2019). "Angular Sizes, Radii, and Effective Temperatures of B-type Stars from Optical Interferometry with the CHARA Array" . The Astrophysical Journal . 873 (1): 91. Bibcode :2019ApJ...873...91G . doi :10.3847/1538-4357/ab04b2 .
^ Zorec, J.; et al. (2009). "Fundamental parameters of B supergiants from the BCD system. I. Calibration of the (λ_1, D) parameters into Teff" . Astronomy and Astrophysics . 501 (1): 297– 320. arXiv :0903.5134 . Bibcode :2009A&A...501..297Z . doi :10.1051/0004-6361/200811147 . S2CID 14969137 .
^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 11 日 Archived 2012-02-04 at the Wayback Machine
External links