Sharaf al-Dīn al-Ṭūsī
Born Ṭūs, (Ira), circa1135
Died (Iran), 1213
Although Sharaf al-Dīn al-Ṭūsī is known especially for his mathematics (in particular his novel work on the solutions of cubic equations), he was also the inventor of the linear astrolabe, a tool that derives from the planispheric astrolabe but is more easily constructed. From his name we may infer that Sharaf al-Dīn was born in the region of Ṭūs, in northeastern Iran. He spent a major part of his early career as a teacher of the sciences, including astronomy and astrology, in Damascus and Aleppo; he also taught in Mosul. Among his students was Kamāl al-Dīn ibn Yūnus, who would eventually teach Sharaf’s namesake, the great Naṣīr al-Dīn al-Ṭūsī.
Sharaf al-Dīn al-Ṭūsī devoted several treatises to the linear astrolabe, sometimes called the staff of al-Ṭūsī. Its principle is simple – many of the important circles on the planispheric astrolabe, especially the almucantars (altitude circles) and the circles of declination, are centered on the...
- Al-Tūsī, Sharaf al-Dīn (1986). Oeuvres mathématiques: Algèbre et géométrie au XIIe siècle, edited and translated by Roshdi Rashed. 2 Vols. Paris: Les Belles Lettres.Google Scholar
- Carra de Vaux, R. (1895). “L’astrolabe linéaire ou bâton d’al-Tousi.” Journal asiatique, 9th ser., 5: 464–516.Google Scholar
- — (1947). Traité de l’astrolabe. Paris: Gauthier-Villars.Google Scholar