Editing Variable-star designation (section)

==History==

In the early 19th&nbsp;century few variable stars were known, so it seemed reasonable to use the letters of the [[Latin script]]. Because very few constellations contained stars with uppercase Latin-letter Bayer designation greater than [[Q Carinae|Q]], the letter R was chosen as a starting point so as to avoid confusion with letter spectral types or the (now rarely used) Latin-letter Bayer designations. Although [[Nicolas Louis de Lacaille|Lacaille]] had used uppercase R–Z&nbsp;letters in a few cases, for example X&nbsp;Puppis (HR&nbsp;2548), these designations were either dropped or accepted as variable star designations.<ref name=wagman/> The star T&nbsp;Puppis was accepted by Argelander as a variable star and is included in the [[General Catalogue of Variable Stars]] with that designation but is now classed as non-variable.<ref name=coelum/>

This variable star [[Astronomical naming conventions|naming convention]] was developed by [[Friedrich Wilhelm Argelander|Friedrich W. Argelander]]. There is a widespread belief according to which Argelander chose the letter&nbsp;R for [[German language|German]] ''rot'' or [[French language|French]] ''rouge'', both meaning "red", because many variable stars known at that time appear red.<ref name=chapman/> However, Argelander's own statement disproves this.<ref name=cds/>

By 1836, even the letter&nbsp;S had only been used in one constellation, [[Serpens]]. With the advent of photography the number of variables piled up quickly, and variable star names soon fell into the Bayer-trap of reaching the end of the alphabet while still having stars to name.{{citation needed|date=April 2020}} After two subsequent supplementary double-lettering systems hit similar limits, numbers were finally introduced.<ref name=cds/>

As with all categories of astronomical objects, names are assigned by the [[International Astronomical Union]] (IAU). The IAU delegates the task to the [[Sternberg Astronomical Institute]] and the [[Institute of Astronomy of the Russian Academy of Sciences]] in Moscow, Russia. Sternberg publishes the ''General Catalog of Variable Stars'' ({{sc|GCVS}}), which is amended approximately once every two years by the publication of a new ''Name-List of Variable Stars''.<ref name=sternberg/> For example, in December&nbsp;2011, the 80th ''Name-List of Variable Stars'', Part&nbsp;II, was released, containing designations for 2,161&nbsp;recently discovered variable stars, which brought the total number in the {{sc|GCVS}} to 45,678&nbsp;variable stars. Among the newly designated objects were V0654&nbsp;Aurigae, V1367&nbsp;Centauri, and BU&nbsp;Coronae Borealis.<ref name=namelist/>