Zeta Aurigae is an eclipsing binary star system in the northern constellation of Auriga. Its name is a Bayer designation that is Latinized from ζ Aurigae, and abbreviated Zeta Aur or ζ Aur. Based upon stellar parallax measurements, this system is approximately distant from the Sun.[ It has a combined apparent visual magnitude of 3.75,][ which is bright enough to be seen with the naked eye. The system is drifting further away from the Sun with a radial velocity of +12 km/s.][
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The two components are designated Zeta Aurigae A and B. The bright giant or supergiant component A has the official name Saclateni, pronounced ,
Nomenclature
ζ Aurigae (Latinised to Zeta Aurigae) is the system's Bayer designation. The designations of the two components as ζ Aurigae A and B derive from the convention used by the Washington Multiplicity Catalog (WMC) for Star system, and adopted by the International Astronomical Union (IAU).
The system bore the traditional names Haedus I (also Hoedus) and Sadatoni (rarely Saclateni).[ It was one of the two haedi (Latin: 'kids') of the she-goat Capella, the other being Haedus II, Eta Aurigae. The name Sadatoni is from the Arabic الساعد الثاني as-sācid aθ-θānī "the second arm (of the charioteer)". The rare traditional name Azaleh is shared (in the form Hassaleh) with Iota Aurigae.][ In 2016, the IAU organized a Working Group on Star Names (WGSN)]
In Chinese, 柱 (Zhù), meaning Pillars, refers to an asterism consisting of Zeta Aurigae, Epsilon Aurigae, Eta Aurigae, Upsilon Aurigae, Nu Aurigae, Tau Aurigae, Chi Aurigae and 26 Aurigae.[ Consequently, the Chinese name for Zeta Aurigae itself is 柱二 (Zhù èr, .)][
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Properties
Zeta Aurigae was first recognized as a spectroscopic binary by William Hammond Wright while analyzing photographic plates taken at Lick Observatory between 1898 and 1908. This star is among those earlier described by Antonia Maury as having a composite spectrum.
The orbital plane of this eclipsing system is oriented close to the line of sight from the Earth, with an inclination estimated as 87.0°.[ As a result, an eclipse of one star by the other occurs during each orbit, causing the net magnitude to decrease to +3.99. The pair have an orbital period of and an eccentricity (ovalness) of 0.4.][ The primary, component A, has been categorized as a K-type star bright giant or supergiant star. Its companion, component B, is a B-type main-sequence star with a stellar classification B5 V or B7 V.][ Because component B has a much hotter photosphere than component A, component B produces most of the system's ultraviolet light. This causes the brightness change seen during the eclipses (when B is obscured) to be much greater in ultraviolet light than it is in visible light.
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[ origin: STI]
[ 香港太空館 - 研究資源 - 亮星中英對照表 , Hong Kong Space Museum. Accessed on line November 23, 2010.]
[ 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, .]
[ Zeta Aurigae's database entry at VizieR.]
External links
