Bharatiya Jyotihshastra (History of Indian Astronomy), translated by R. V. Vaidya v2.c12.s2.t86.2

v2.c12.s2.t86.2

The Arab astronomers AL FAZARI, YAKUB-BIN-TĀRIQUE, and ABU AL HĀSĀN, lived in the latter half of the 8th century A. D. They compiled astronomical works in Arabic with the help of the Indian astronomers referred to above. These works are not at present available; still Beruni had with him the works written by these three astronomers. He has often referred to the works written by the first two. Those works contained several of the following subjects usually found in Sanskrit works, viz. measures of time, numbers of the revolutions of planets in Mahāyuga or Kalpa ; lengths (in yojanas of planetary orbits, calculation of ahargaṇa for finding the mean positions) of planets ; sines of angles ; rising and setting of planets ; first visibility of the moon, etc. The Arabs first learnt astronomy from the Hindus and then they came to know of Ptolemy's work. Al Fazari was the first to teach Hindu astronomy to Mahomedans. The Khaṇḍakhādya had already been translated into Arabic when Yakub compiled his work. That translation may have been made by Al Fazari.