An Examination of Al-Bīrūnī’s Knowledge of Indian Astronomy

Abstract

By the time al-Bīrūnī wrote the KH (see al-Bīrūnī’s books; see also Boilot 1960; Kennedy 1970; Khan, A.S. 1982; Khan M.S. 1975) in the first half of the eleventh century, Greek astronomy specially the Almagest of Ptolemy was fully diffused among the Arabs. They also had some knowledge of Persian astronomy (Pingree 1963)- But he was not the first Muslim scientist to write on Indian astronomy. Before he visited India (around 408/1017) he had some knowledge of this subject derived from Arabic translations of Sanskrit astronomical works. He records that the Brāhmasphuṭa-siddhānta of Brahmagupta (ca. A.D. 598) was translated by the order of Caliph Manṣūr of Baghdad (754-775 A.D.) in 154/771 or in 156/77_3(KH, p.351) and its Arabic translation was called Sindhind al-Kabīr or the Great Sindhind. He adds that he translated it into Arabic and wrote a treatise on it. He also studied its method of calculation in his treatise Tarjumah mā fī Brāhma Siddhānd min Ṭuruq al-Ḥisab (Khan, A.S.1982, p.20). Al-Bīrūnī states that he also retranslated the Khaṇḍakhādyaka by Brahmagupta, called in Arabic al-Arkand and published a new correct translation (KH, pp.346-383; Nalino 1911, p.83; Nadwi 1930, p. 139). He had written a treatise entitled Tahddhīb zīj al-Arkand in which he corrected its errors but this is not available at present (Khan, A.S. 1982, No.6, p.12). The Āryabhatīya of Āryabhata (b. A.D. 476) called Arjabhadh in Arabic was translated by Abu’l-Hasan al-Ahwāzī and it was perhaps available to al-Bīrūnī(KH, p.357; Pingree 1970, p.308; Nalino 1911, p.172-73).