Aryabhata was a great mathematician and astronomer who was born in 476 CE in Bihar, India and died in 550 CE. His most famous works are the Aryabhatiya and the Arya-siddhanta.
Aryabhatiya is a compendium of math and astronomy. Unlike many of Aryabhata's work, this compendium has survived to modern times. It covers subjects from arithmetic to spherical trigonometry. In terms of astronomy, Aryabhata explained eclipses, sidereal periods and heliocentrism.
Aryabhata's work continues to influence the Indian astronomical tradition. His works in astronomy are still widely used in the Islamic world, such as the use of the Jalali calendar, which is based on the actual solar transit that was discovered and explained by Aryabhata. He also has a satellite named in his honor.