Aaryabhatta

Aaryabhatta (AD 476 – 550) is the first in the line of great mathematician-astronomers from the classical age of Indian mathematics and Indian astronomy. Aryabhata is the father of the Decimal number system which has become universal today. His most famous works are the Aryabhatiya (AD 499 at age of 23 years) and Arya-Siddhanta.

Though Aryabhata's year of birth is clearly mentioned in Aryabhatiya, exact location of his place of birth remains a matter of contention amongst the scholars. Some believe he was born in the region lying between Narmada and Godavari, which was known as Ashmaka and they identify Ashmaka with central India; while other texts describe the Ashmakas as having fought Alexander, which would put them further north.

Aryabhata is the author of several treatises on mathematics and astronomy, some of which are lost. His major work, Aryabhatiya, a compendium of mathematics and astronomy, was extensively referred to in the Indian mathematical literature, and has survived to modern times. The mathematical part of the Aryabhatiya covers arithmetic, algebra, plane trigonometry and spherical trigonometry.

It also contains continued fractions, quadratic equations, sums of power series and a table of sines. The Arya-siddhanta, a lost work on astronomical computations, is known through the writings of Aryabhata's contemporary Varahamihira, as well as through later mathematicians and commentators including Brahmagupta and Bhaskara.

This work appears to be based on the older Surya Siddhanta, and uses the midnight-day-reckoning, as opposed to sunrise in Aryabhatiya. This also contained a description of several astronomical instruments, the gnomon (shanku-yantra), a shadow instrument (chhaya-yantra), possibly angle-measuring devices, semi-circle and circle shaped (dhanur-yantra / chakra-yantra), a cylindrical stick yasti-yantra, an umbrella-shaped device called chhatra-yantra, and water clocks of at least two types, bow-shaped and cylindrical.

A third text that may have survived in Arabic translation is the Al ntf or Al-nanf, which claims to be a translation of Aryabhata, but the Sanskrit name of this work is not known. Probably dating from the ninth b.c., it is mentioned by the Persian scholar and chronicler of India, Abu Rayhan al-Biruni.

Aryabhata's work was of great influence in the Indian astronomical tradition, and influenced several neighbouring cultures through translations. Aryabhata's astronomical calculation methods were also very influential.

(All info and picture taken from net)*