Varāhamihira

Varāhamihira (c. 20/21 March 505 – c. 587), also called Varāha or Mihira, was an ancient Indian mathematician and astronomer who lived in Ujjain (ancient Avanti region in present-day Madhya Pradesh, India. He is considered one of the foremost scholars of classical Indian astronomy. He mastered the three divisions (skandhatraya) of Jyotiṣa: mathematical astronomy (gaṇita), natural sciences (saṃhitā), and horoscopy (horā). His masterwork, the Pañcasiddhāntikā (treatise on five siddhāntas), is the primary surviving historical record of ancient Indian astronomical systems. His mathematical contributions include methods for computing sine tables and early trigonometric techniques and works on combinators.

Notable works: Brihat Jataka, Brihat-Samhita, Pancha-siddhantika

Source: Wikipedia — https://en.wikipedia.org/wiki/Var%C4%81hamihira