Āryabhaṭa (Devanāgarī: आर्यभट) (AD 476 – 550) is the first of the great mathematician-astronomers of the classical age of Indian mathematics and Indian astronomy. He was born at Muziris (the modern day Kodungallour village) near Thrissur, Kerala. Available evidence suggest that he went to Kusumapura for higher studies. He lived in Kusumapura, which his commentator Bhāskara I (AD 629) identifies as Pataliputra (modern Patna). K. Chandra Hari, a senior geoscientist at the Institute of Reservoir Studies of Oil and Natural Gas Commission, Ahmedabad has refuted this popular opinion and claims that based on his interpretation of Aryabhatta's system of measurements and writings, it is highly likely that he belonged to the modern Ponnani-Chamravattom area (latitude 10N51 and longitude 75E45) in Kerala in the 6th Century AD
Aryabhata was the first in the line of brilliant mathematician-astronomers of classical Indian mathematics, whose major work was the Aryabhatiya and the Aryabhatta-siddhanta. The Aryabhatiya presented a number of innovations in mathematics and astronomy in verse form, which were influential for many centuries. The extreme brevity of the text was elaborated in commentaries by his disciple Bhaskara I (Bhashya, ca. 600) and by Nilakantha Somayaji in his Aryabhatiya Bhasya, (1465). The number place-value system, first seen in the 3rd century Bakhshali Manuscript was clearly in place in his work.[1] He may have been the first mathematician to use letters of the alphabet to denote unknown quantities.[2]
Aryabhata's system of astronomy was called the audAyaka system (days are reckoned from uday, dawn at lanka, equator). Some of his later writings on astronomy, which apparently proposed a second model (ardha-rAtrikA, midnight), are lost, but can