al-Lum'a fi hall al-kawakib al-sab'a (al-Kawm al-Rishi)

Al-Lum'a fi hall al-sab'a, also known as al-Lum'a fi hall al-kawakib al-sab'a (al-Azhar Library no. 493/71513), is a treatise in which al-Kawm al-Rishi takes up Ibn al-Shatir's zij, abridging it and correcting what he saw as errors. ^{1 2} He first called it Nuzhat al-nazir fi talkhis zij Ibn al-Shatir, or in another version Nuzhat al-nazir fi tashih usul Ibn al-Shatir, then abridged it and named it al-Lum'a. ²

It contains tables for deriving the Arab, Coptic, Byzantine and Persian eras and their months and converting between them, the seasons of fasting and feasts, tables for the sun, moon and five planets, for eclipses and crescent visibility, for the positions of the fixed stars, and for the longitudes and latitudes of towns. ² It attracted many commentaries, among them that of Shaykh Muhammad al-Khudari. ²