**Birth:**836

**Death:**901

Known for his work on mechanics, astronomy, pure mathematics and geometry.
Ibn Qurrah was a pioneer in extending the concept of traditional geometry to geometrical algebra and proposed theories that led to the development of non-Euclidean geometry, spherical trigonometry, integral calculus and real numbers. He used arithmetic terminology to study several aspects of conic sections (parabola and ellipse). His algorithm for computing the surface area and volume of solids is in fact what we came to know later as the integral calculus.
Ibn Qurrah's original work on Mechanics and Physics involves examining conditions of equilibrium of bodies, beams and levers. Some historians have recognised him as the Founder of Static's.
Ibn Qurrah added the ninth sphere to Ptolemic astronomy, and analysed several problems on the movements of sun and moon and wrote treatises on sundials. Beer and Madler in their famous work Der Mond (1837) mention a surface feature of the moon after Thebit (Thabit or Ibn Qurrah).
Thabit's books on mathematics, astronomy and medicine have survived. He translated many Greek and Syrian works on science into Arabic while in the service of Caliph al-Mu'tadid.
Thabit Ibn Qurrah, known in the west as Thebit, whose full name was Thabit Ibn Qurrah Ibn Marwan al-Harrani was born in Harran (Turkey) and died in Baghdad.

Compiled by:*M. Nauman Khan*