Thabit al-Sabi al-Harrani Ibn Qurra

Thabit Ibn Qurra, one of the most famous and prominent Muslim astronomers and mathematicians who flourished in Baghdad.

Thabit Ibn Qurra Ibn Marwan al-Sabi al-Harrani was born in the year 836 C.E. at Harran (present Turkey). He was a Muslim astronomer and mathematician. In Latin he was known as Thebit.

Mohamed Ibn Musa Ibn Shaker the great Muslim mathematician, impressed by his knowledge of languages, and realizing his potential for a scientific career, choose him to join the scientific group at Baghdad that was being patronized by the Abbasid Caliphs.

In Baghdad he was taught on the hands of the famous Banu Musa brothers. In this way Thabit was able contribute in several branches of science, notably mathematics, astronomy and mechanics, in addition to translating a huge number of works from Greek to Arabic. Later Thabit's patron was the Abbasid Caliph al-M'utadid and Thabit very soon became his personal friend and the visitor of his court.

The majority of his contributions lie in mathematics and astronomy. He was instrumental in extending the concept of traditional geometry to geometrical algebra and proposed several theories that led to the development of non-Euclidean geometry, spherical trigonometry, integral calculus and real numbers. He criticized a number of theorems of Euclid's elements and proposed important improvements. He applied arithmetical terminology to geometrical quantities, and studied several aspects of conic sections, notably those of parabola and ellipse. A number of his computations aimed at determining the surfaces and volumes of different types of bodies and constitute, in fact, the processes of integral calculus, as developed later.

In astronomy he was one of the early reformers of Ptolemaic views. He solved many problems related to the movements of sun and moon and he also wrote books on sundials.

In the fields of mechanics and physics he may be recognized as the establisher of static. He examined conditions of equilibrium of bodies, beams and levers.

Not only did he translate a large number of books himself, but he also founded a school of translation and supervised the translation of a further large number of books from Greek to Arabic.

Among Thabit's writings a large number have survived, while several are not extant. Most of the books are on mathematics, followed by astronomy and medicine. The books have been written in Arabic but some are in Syriac, which was the eastern Aramaic dialect from Odessa. In the middle Ages, Gherard of Cremona translated some of his books into Latin. In recent centuries, a number of his books have been translated into European languages and published.

He carried further the work of the Banu Musa brothers and later his son and grandson continued in this tradition, with the help of other members of the group. In the 9th century His original books as well as his translations accomplished a positive influence on the development of subsequent scientific research.

After a long career of scholarship, Thabit died at Baghdad in 901 C.E.