Varahamihira

Varahamihira (c. 505-587 CE) was an Indian astronomer, mathematician and astrologer active during the Gupta era, traditionally associated with the city of Ujjain, a leading center of astronomical study in ancient India. His treatise the Pancha-siddhantika summarizes and compares five earlier astronomical systems then in use in India, including ones showing clear influence from Hellenistic Greek astronomy, making it a key source for understanding the cross cultural transmission of astronomical knowledge in the ancient world. His other major work, the Brihat Samhita, is a wide ranging encyclopedic text covering astronomy, astrology, architecture, agriculture, gemology and numerous other practical and natural subjects, reflecting the broad, unified conception of natural knowledge characteristic of the period. His astronomical and mathematical writings were influential on later Indian astronomers for centuries.