Alpha Trianguli
star in the constellation Triangulum
Alpha Trianguli (α Trianguli, abbreviated Alpha Tri, α Tri) is a triple star system in the constellation of Triangulum. Based on parallax measurements obtained during the Hipparcos mission, it is approximately 63.3 light-years (19.4 parsecs) distant from the Sun. The brighter or primary component is named Mothallah .
Nomenclature
α Trianguli (Latinised to Alpha Trianguli) is the system's Bayer designation.
The system bore the traditional names Ras al Muthallah or Mothallah and Caput Trianguli derived from the Arabic رأس المثلث' raʼs al-muthallath "the head of the triangle" and its Latin translation. The International Astronomical Union Working Group on Star Names (WGSN) has approved the name Mothallah for this star. For members of multiple star systems, and where a component letter (e.g. from the Washington Double Star Catalog) is not explicitly shown in the namelist, the WGSN says that the name should be understood to be attributed to the visually brightest component by visual brightness.
In combination with Beta Trianguli, these stars were called Al Mīzān, which is Arabic for "The Scale Beam".
In Babylonian astronomy, Alpha Trianguli is listed as UR.BAR.RA "The Wolf", bearing the epithet "the seeder of the plough" in the MUL.APIN, listed after "The Plough", the name for a constellation formed of Triangulum plus Gamma Andromedae.
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This entry incorporates text from “Alpha Trianguli” 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.