Al-Bitruji proposed a theory on planetary motion in which he wished to avoid both epicycles and eccentrics,[5] and to account for the phenomena peculiar to the wandering stars, by compounding rotations of homocentric spheres.
It was suggested based on the Latin translations that his system is an update and reformulation of that of Eudoxus of Cnidus combined with the motion of fixed stars developed by al-Zarqālī.
[1] Al-Bitruji wrote Kitāb al-Hayʾah (Arabic: 'كتاب الهيئة, romanized: Book of the Structure), which presented criticism of Ptolemy's Almagest from a physical point of view.
[4] This work was translated into Latin by Michael Scot in 1217 as De motibus celorum [7] (first printed in Vienna in 1531).
[4] There is also an anonymous treatise on the tides (Escorial MS 1636, dated 1192), which contains material seemingly borrowed from al-Bitruji.