Delta Arietis is a star in the northern constellation of Aries, positioned 1.8 degrees north of the ecliptic. Its identifier is a Bayer designation that is Latinized from δ Arietis, and abbreviated Delta Ari or δ Ari. This star is officially named Botein, pronounced . The apparent visual magnitude of Delta Arietis is 4.35, so it is visible to the naked eye. It has an annual parallax shift of ; corresponding to a distance of about from the Sun. This star is receding from the Sun with a radial velocity of +23 km/s.
Nomenclature δ Arietis (Latinised to Delta Arietis) is the star's Bayer designation.
It bore the traditional name Botein which is derived from Al Bīrūnī's Al Buṭayn (Arabic: البُطَين), the diminutive of Al Baṭn, "the Belly". This is the name of a star association consisting of this star, Epsilon Arietis, Zeta Arietis, Pi Arietis, and Rho3 Arietis According to a 1971 NASA catalogue of stars, Al Buṭain was the title for five stars: Delta Arietis (listed as Botein), Pi Arietis (as Al Buṭain I), Rho3 Arietis (Al Buṭain II), Epsilon Arietis (Al Buṭain III) and Zeta Arietis (Al Buṭain IV). In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalogue and standardize proper names for stars. The WGSN approved the name Botein for this star on 12 September 2016 and it is now so included in the List of IAU-approved Star Names.
In the catalogue of stars in the Calendarium of Al Achsasi Al Mouakket, this star was designated Nir al Botain, which was translated into Latin as Lucida Ventris, meaning "the brightest of the belly".
In Chinese, (), meaning Yin Force, refers to an asterism consisting of Delta Arietis, 63 Arietis, Zeta Arietis, Tau Arietis and 65 Arietis. 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, the Chinese name for Delta Arietis itself is (, .) 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.
Properties Delta Arietis is an evolved giant star with a stellar classification of K2 III. It belongs to a population known as red clump giants, which means it is generating energy through the fusion of helium at its core. With 1.9 times the mass of the Sun and 1.3 billion years old, the photosphere has expanded until it is around 10.1 times the Sun's radius. The star shines with 52.7 times the Sun's luminosity at an effective temperature of 4,782 K, giving it the orange-hued glow of a K-type star. It is a suspected variable star that ranges in magnitude from 4.33 to 4.37.
References
External links HR 951 The Constellations and Named Stars Image Delta Arietis