Kappa Aquarii
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Kappa Aquarii is a candidate binary star in the equatorial constellation of Aquarius. Its identifier is a Bayer designation that is Latinized from κ Aquarii, and abbreviated Kappa Aqr or κ Aqr, respectively. This system is visible to the naked eye, but it is faint at an apparent visual magnitude of 5.03.<ref name=Soubiran_et_al_2022/> Based upon parallax measurements, it is around Template:Convert from the Sun.<ref name=aass34_1/> The system is drifting further away from the Sun with a radial velocity of +7.3 km/s.<ref name=aj135_1_209/>
The two components are designated Kappa Aquarii A and B. The former is named Situla, pronouced Template:IPAc-en, the traditional name for the system.<ref name="IAU-LSN"/>
Nomenclature
κ Aquarii (Latinised to Kappa Aquarii) is the system's Bayer designation. The designations of the two components as Kappa Aquarii A and B derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU).<ref name="planetnaming"/>
It bore the traditional name Situla, a Latin word meaning "bucket" or "water jar".<ref name=allen1963/> In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)<ref name="WGSN"/> to catalogue and standardize proper names for stars. The WGSN decided to attribute proper names to individual stars rather than entire multiple systems.<ref name="TriRpt18"/> It approved the name Situla for the component Kappa Aquarii A on 12 September 2016 and it is now so included in the List of IAU-approved Star Names.<ref name="IAU-LSN"/>
In Chinese, {{#invoke:Lang|lang}} ({{#invoke:Lang|lang}}), meaning Temple, refers to an asterism consisting of Kappa Aquarii, 44 Aquarii, 51 Aquarii and HD 216718.<ref>Template:In lang 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, Template:ISBN.</ref> Consequently, the Chinese name for Kappa Aquarii itself is {{#invoke:Lang|lang}} ({{#invoke:Lang|lang}}, Template:Langx).<ref>Template:In lang 香港太空館 - 研究資源 - 亮星中英對照表 Template:Webarchive, Hong Kong Space Museum. Accessed on line November 23, 2010.</ref> From this Chinese name, the name Heu Leang has appeared, meaning "the empty bridge".<ref name=allen1963/>
Properties
Kappa Aquarii is most probably a wide binary star system.<ref name=mnras389_2_869/> The brighter component is a giant star with a stellar classification of Template:Nowrap.<ref name=Keenan_McNeil_1989/> It has exhausted the supply of hydrogen at its core and has expanded to 13<ref name=aj135_1_209/> times the radius of the Sun. It is radiating 60<ref name=aj135_1_209/> times the Sun's luminosity from its photosphere at an effective temperature of Template:Val,<ref name=aj135_1_209/> giving it the orange-hued glow of a K-type star.<ref name=csiro/>
The fainter companion star is located at an angular separation of 98.3 arcseconds and has an apparent magnitude of 8.8.<ref name=csiro/>
In culture
Endymion, an 1818 poem by John Keats, describes the star in its form as a water urn thus: Template:Quote
USS Situla (AK-140) was a United States Navy Crater-class cargo ship named after the star.