High Middle Ages · Middle East · Science
1289
Fakhr al-Din al-Khalili advances trigonometry
1289
Mathematicians working in the tradition of Nasir al-Din Tusi at Maragheh refined trigonometric tables to unprecedented precision, computing sine values to ten sexagesimal places. These tables, circulated in Persian and Arabic, would underpin astronomical calculation from Isfahan to Samarkand for the next two centuries. The precision of their calculations remained unmatched in Europe until the sixteenth-century work of Rheticus and the Viennese school.