Biography of Abu Reyhan Al-Biruni:

Abu al-Rayhan Muhammad ibn Ahmad al-Biruni (973–1048) was one of the greatest scholars of the Islamic Golden Age. He was an Iranian astronomer, mathematician, and philosopher, whose explorations and discoveries along with those of other great scientists, have established the grounds of modern science. Al-Biruni was born in Kath, a district of Khwarezm (now a part of Uzbekistan). His family background also took interest in the studies of science as well, which made him grew up in an environment encouraging to his interests. He was the first who able to obtain a simple formula for measuring the Earth's radius. Moreover, he thought possible the Earth revolving around the Sun and developed the idea that the geological eras succeed one to another.

Biruni is the author of about 145 books, in which more than 90 of them is devoted to astronomy, mathematics, and related to themes mathematical geography. Although his main concern in astronomy was for computations, he also devoted attention to theoretical problems. Al-Biruni's major contribution to astronomy is al-Qanun al-masʿudi fi'l-hayʾa wa'l-nojum (Masʿudic canon of astronomy), covering the same ground as Ptolemy's Almagest but introducing new material. Most of al-Biruni's original theoretical concepts are to be found in this work.

Like the Almagest, the Qanun contains theoretical derivations of astronomical parameters, as well as tabular functions to facilitate the computation of planetary positions. It thus differs from the works of most of al-Biruni's predecessors and contemporaries who were concerned only with constructing astronomical tables (zīj) suitable for computation of planetary positions, usually without any discussion of the derivation of the parameters upon which the tables were based. During his 75 years lifetime, al-Biruni succeeded to revolutionize the way numerous subjects were understood. His intelligence and the capacity of mastering various subjects, and his ability to relate them together to gain a better understanding of each, puts him among the greatest Muslim and Iranian scientists of all time.