The Book of Fixed Stars (كتاب صور الكواكب , literally The Book of the Shapes of Stars) is an astronomical text written by Abd al-Rahman al-Sufi (Azophi) around 964. Following the translation movement in the 9th century AD, the book was written in Arabic, the common language for scholars across the vast Islamic territories, although the author himself was Persian. It was an attempt to create a synthesis of the comprehensive star catalogue in Ptolemy’s Almagest (books VII and VIII) with the indigenous Arabic astronomical traditions on the constellations (notably the Arabic constellation system of the Anwā’). The original manuscript no longer survives as an autograph, however, the importance of tradition and the practice of diligence central to Islamic manuscript tradition have ensured the survival of the Book of Stars in later-made copies.
The treatise was written in the Persian city of Shiraz, for the patron and Buyid emir ‘Adud al-Dawla. Although al-Sufi made his longitudinal calculations correct for the year 964 only, the work remained highly influential, functioning as the standard text on Arabic astronomy to be consulted in all Islamic territories and faithfully copied for many centuries after its production. Since it was only correct for the single year of 964, the Book of Fixed Stars was intended to serve a broader educational purpose, rather than being concerned with the mathematical technicalities of astronomy.
The Book of Fixed Stars is representative of the concerns of Islamic scholars during the late-9th to 11th centuries, where following the translation of Hellenistic texts from Greek to Arabic, "Islamic astronomers and astrologers concentrated on analyzing, criticizing, and perfecting the geometrical models of Ptolemy". Medieval Islamic astronomers also drew from Sanskrit and Middle Persian sources to learn "methods for calculating the position of heavenly bodies, and for creating tables recording the movement of the sun, the moon, and the five known planets.