Alderamin

The IAU catalogue's account

Applied to α Cep since medieval times. The erroneous derivation understood since Early Modern times was from al-dhira (al-)yamin, "the Right Forearm," an assumed Arabic descriptive term for α Cep. Firstly, in the Almagest, α Cep is described on the right "shoulder" (Arabic al-katif or al-mankib) of Cepheus, whereas no right "forearm" (al-dhira<) is described for the figure. Secondly, in Arabic, "right forearm" is spelled correctly as al-dhira al-yumna, which (in contrast to al-yamin) lacks assonance in the last syllable to Alderamin. Therefore, it is more likely that Alderamin is derived from the various medieval Christian abbreviations of muqaddam al-dhira<ain, "the Preceding One of the Two Cubits, or Forearms," which was a name for the Arabic Almagest period (based on pre-Islamic Arabian) for α Gem. This would have been wrongly transferred to α Cep in medieval times.

Source language

Arabic

Reference

Kunitzsch, Paul; Smart, Tim (2006). A Dictionary of Modern star Names: A Short Guide to 254 Star Names and Their Derivations (2nd rev. ed.). Cambridge, Massachusetts: Sky Pub.

Source: IAU Catalog of Star Names (IAU-CSN), Working Group on Star Names. The account is the IAU's own text and is quoted in full: it is published under CC BY.