The famous Iranian Islamic religious scholar and scientist Khwaja Naseer od-Din Tousi
Compiled By: Syed Ali Shahbaz
On18th of the Islamic month of Zil-Hijjah in 672 AH, the famous Iranian Islamic religious scholar and scientist, Mohammad ibn Mohammad ibn Hasan Tousi, popularly known as Khwaja Naseer od-Din, passed away at the age of around 75 in Kazemain, Iraq, and was laid to rest in the holy mausoleum of Imam Musa al-Kazem (AS), the 7th Infallible Successor of Holy Prophet Mohammad (SAWA).
Born in the city of Tous, near the holy city of Mashhad in Khorasan, northeastern Iran, he was an outstanding philosopher, scientist, mathematician and astronomer, who made outstanding contributions to world culture and civilization. Even the Mongol invaders acknowledged his genius and Hulagu Khan, appointed him as his scientific advisor.
Naseer od-Din Tousi built the famous observatory at Maragheh. It had various instruments such as a 4-meter wall quadrant made from copper and an azimuth quadrant which was his unique invention. Using accurately plotted planetary movements, he modified Ptolemy's model of the planetary system based on mechanical principles. The observatory and its library became a centre for a wide range of work in science, mathematics and philosophy.
He wrote some 80 books on various subjects including theology, ethics, philosophy, mathematics, science, astronomy, etc, in both Arabic and Persian.