AlShatirs

Al-Shatirs refers to the circle of medieval Islamic astronomers centered on the Damascus-based scholar Ibn al-Shatir and to the body of work associated with him. Active in the 14th century during the Mamluk period, Ibn al-Shatir (often dated around 1304–1375) is the best known figure in this tradition, but the term also encompasses his collaborators and the manuscripts attributed to the group. The most prominent of these works is the Zij al-Shatiri, a comprehensive set of astronomical tables and explanatory material intended to compute planetary positions with improved precision.

Contributions and methods include a geocentric planetary model that seeks to remove the Ptolemaic equant. The al-Shatirs employed a system of nested epicycles and deferents designed to maintain uniform circular motion while reproducing observed planetary motions. Their solar, lunar, and planetary theories build on earlier Ptolemaic and Maragha (Tusi) ideas but introduce refinements that reduce or eliminate the need for the equant. The models emphasize mechanical plausibility and geometric construction, often with diagrams and detailed calculation rules.

Influence and legacy are a subject of scholarly discussion. The al-Shatirs’ work is regarded as part of the broader Islamic astronomical tradition that influenced later developments in the region and has been cited in debates about the transmission of ideas to Europe. Some historians note similarities between Shatiri mechanisms and later Copernican concepts, alleging possible indirect influence through Latin translations or manuscript circulation, while others caution that such connections are conjectural.

Manuscripts and scholarship continue to be studied, with key texts preserved in libraries in the Middle East and Europe. Modern editions and translations help illuminate the technical innovations of the al-Shatirs and their role in the history of astronomical modeling.