Abū Muḥammad 'Abd al-Jabbār al-Kharaqī, Persian : بهاءالدین ابوبکر محمد بن احمد بن ابوبشر also Al-Kharaqī (1084-1158 [1] ) was a Persian [2] astronomer and mathematician of the 12th century, born in Kharaq near Merv. [3] He was in the service of Sultan Sanjar at the Persian Court. Al-Kharaqī challenged the astronomical theory of Ptolemy in the Almagest , and established an alternative theory of the spheres, imagining huge material spheres in which the planets moved inside tubes. [3] He later wrote at-Tabṣıra fî ʿilmi’l-hayʾa as a second edition to his well-known book Muntahā al-idrāk fī taqāsīm al-aflāk in which he removed some parts and reshaped its structure as two parts instead of three. [1]
During his travels to the Ottoman Empire in 1536, Guillaume Postel acquired an astronomical work by al-Kharaqī, Muntahā al-idrāk fī taqāsīm al-aflāk ("The Ultimate Grassp of the Divisions of Spheres"), annotated it, and brought it back to Europe. [4]
Al-Kharaqī also wrote mathematical treatises, now lost, Al-Risala al-Shāmila ("Comprehensive Treatise") and Al-Risala al-Maghribiyya ("The North African Treatise", related to the calculus of dirham and dinar). [3]
