Qāḍī Zāda al-Rūmī

Qāḍī Zāda al-Rūmī (1364 in Bursa, Ottoman Empire – 1436 in Samarqand, Persia), whose actual name was Salah al-Din Musa Pasha (qāḍī zāda means "son of the judge", al-rūmī "the Roman" indicating he came from Asia Minor, which was once Roman), was a Turkish astronomer and mathematician who worked at the observatory in Samarkand. He computed sin 1° to an accuracy of 10⁻¹².

Together with Ulugh Beg, al-Kāshī and a few other astronomers Qāḍī Zāda produced the Zij-i-Sultani, the first comprehensive stellar catalogue since the Maragheh observatory's Zij-i Ilkhani two centuries earlier. The Zij-i Sultani contained the positions of 992 stars.

His works

• Sharh al-Mulakhkhas (Commentary on Jaghmini's compendium on the science of Astronomy
• Sharh Ashkal al-Ta'sis (Commentary on Samarkandi's Arithmetics)

Further reading

• Adivar, A. (1943). Osmanli Türklarinde Ilim. Istambul. 
• Ataev, U. (1972). "The commentary of Kazi-zade ar-Rumi on the astronomical treatise of Nasir ad-Din at-Tusi" (in Russian). Questions on the history of mathematics and astronomy I. Trudy Samarkand. Gos. Univ. (N.S.) Vyp. 229: 124–127. 
• Dilgan, H. (1970–80). "Qāḍī Zāda al-Rūmī". Dictionary of Scientific Biography. New York: Charles Scribner's Sons. ISBN 0684101149. 
• O'Connor, John J.; Robertson, Edmund F., "Qadi Zada al-Rumi", MacTutor History of Mathematics archive, University of St Andrews, http://www-history.mcs.st-andrews.ac.uk/Biographies/Qadi_Zada.html .
• Pasaev, Z. A. (1972). "The commentary of Kazi-zade ar-Rumi on the astronomical treatise of al-Djagmini (a brief survey)" (in Russian). Questions on differential equations, number theory, algebra and geometry. Trudy Samarkand. Gos. Univ. (N.S.) Vyp. 202: 202–204. 
• Rozenfel'd, B. A.; A. P. Yushkevich (1960). "The treatise of Qadi Zada al-Rumi on the determination of the sine of one degree" (in Russian). Istor.-Mat. Issled. 13: 33–538. 
• Rozenfel'd, B. A.; A. P. Yushkevich (1960). "Notes on a treatise of Qadi Zada al-Rumi" (in Russian). Istor.-Mat. Issled. 13: 552–556. 

External links

• Ragep, F. Jamil (2007). "Qāḍīzāde al‐Rūmī: Ṣalāḥ al‐Dīn Mūsā ibn Muḥammad ibn Maḥmūd al‐Rūmī". In Thomas Hockey et al. The Biographical Encyclopedia of Astronomers. New York: Springer. p. 942. ISBN 9780387310220. http://islamsci.mcgill.ca/RASI/BEA/Qadizade_al-Rumi_BEA.htm.  (PDF version)