Alpha Aquarii
star in the constellation Aquarius
Alpha Aquarii is a yellow supergiant star in the constellation of Aquarius. Its identifier is a Bayer designation that is Latinized from α Aquarii, and is abbreviated Alf Aqr or α Aqr, respectively. This star has the official name Sadalmelik, pronounced . At an apparent visual magnitude of 2.94, it is the second-brightest star in Aquarius, just marginally fainter than Beta Aquarii. Based upon parallax measurements made by the Gaia spacecraft, it is located at a distance of roughly 690 light-years (210 parsecs). It is drifting further away from the Sun with a radial velocity of 7.5 km/s.
Nomenclature
α Aquarii (Latinised to Alpha Aquarii) is the star's Bayer designation. WDS J22058-0019 A is its designation in the Washington Double Star Catalog.
It bore the traditional name Sadalmelik, which derived from an Arabic expression سعد الملك (sa‘d al-malik), meaning "the lucky [star] of the king". The name Rucbah had also been applied to this star; though it shared that name with Delta Cassiopeiae.
“Alpha Aquarii” enters the record as star in the constellation Aquarius. Crown Archives preserves that source wording while asking what Alpha, Aquarii and star can confirm, complicate or overturn.
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This entry incorporates text from “Alpha Aquarii” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.