Beta Crateris, Latinized from β Crateris, is a binary star[ system in the southern constellation of Crater. It is visible to the naked eye with an apparent visual magnitude of 4.46.][ Based upon an annual stellar parallax of 9.59 milliarcsecond as seen from Earth, it is located around 340 from the Sun.
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This is an astrometric binary[ star system with an orbital period of 6.0 years and a projected separation of 8.3 AU. The orbit has an estimated semimajor axis of 9.3 AU.][ The primary, component A, is listed as an A-type star giant star with a stellar classification of A2 III.][ However, Houk and Smith-Moore (1988) give a main sequence classification of A1 V,][ while Abt and Morrell (1995) list it as a subgiant star with a class of A2 IV.][ The spectrum shows enhanced barium, possibly as a result of a previous mass transfer event.][
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The companion, component B, is a white dwarf[ of class DA with an effective temperature of 36,885 K that has been cooling down for around four million years.][ It has an unusually low mass, 43% that of the Sun, suggesting that the white dwarf progenitor may have transferred matter to its companion. Alternative scenarios require either the evolution of a triple star system, or a binary system with highly eccentric orbit resulting in grazing interactions.][ The dwarf is a source of X-ray astronomy.][
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Name
This star was one of the set assigned by the 16th century astronomer Al Tizini[ Star Names - R.H.Allen p. 182][ Star Names - R.H.Allen p. 246]
According to the catalogue of stars in the Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars, Al Sharāsīf were the title for two stars : β Crateris as Al Sharasīf II and κ Hydrae as Al Sharasīf I.
In Chinese language, 翼宿 (Yì Sù), meaning Wings (asterism), refers to an asterism consisting of β Crateris, Alpha Crateris, Gamma Crateris, Zeta Crateris, Lambda Crateris, Nu Hydrae, Eta Crateris, Delta Crateris, Iota Crateris, Kappa Crateris, Epsilon Crateris, HD 95808, HD 93833, Theta Crateris, HD 102574, HD 100219, HD 99922, HD 100307, HD 96819, χ1 Hydrae, HD 102620 and HD 103462.[ 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, .] Consequently, β Crateris itself is known as 翼宿十六 (Yì Sù shíliù, .)[ AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 31 日 ][ 夢之大地 @ 國立成功大學 WebBBS DreamLand @ National Cheng Kung University WebBBS System]
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