Abu-Rayhan Biruni ( ابوریحان بیرونی ) was Iranian scholar and polymath during Islamic Golden Age. Mathematics, astronomy, physics, natural science and philosophy was his main focuses. He was born in Kath, Khwarezm ( خوارزم ) in 973 C.E. (year 352 in Iranian solar calendar). Kath was located close to Aral sea which is part of Uzbekistan in modern day. Major of his publications (95 out of 146 books/dissertations) are over Astronomy and Mathematical Geography and Applied Mathematics in Astronomy field. Some of his well known works are method for measuring earth radius or developing scientific experimental method for measuring density in mechanics. His publication includes 1) "Masʿudic canon of astronomy" ( al-Qānūn al-Masʿūdī -originally in Arabic-1037 C.E.- قانون مسعودی ) contains theoretical derivations of astronomical tables suitable for computation of planetary positions and some original theoretical concepts. The book is in 3 major chapters and his calculation on radius and circumference of earth is in chapter 2. 2)  al-Tafhim ( originally in Farsi-1029 C.E. التفهیم ) contains instruction over celestial bodies and astrology based on astronomical geometry/trigonometry and arithmetic.