Pañca Siddhāntikā

VārāhaMihira
Born	505 CE
Died	587 CE
Occupation	astronomer, mathematician, and astrologer
Period	Gupta era
Subject	Astronomy, Astrology, Mathematics
Notable works	Pancha-Siddhāntikā, Brihat-Samhita, Brihat Jataka

Vārāhamihira  pronunciation  (505–587 CE), also called Vārāha or Mihira, was an Indian astronomer, mathematician, and astrologer who lived in Ujjain. He was born in the Avanti region, roughly corresponding to modern-day Malwa, to Adityadasa, who was himself an astronomer. According to one of his own works, he was educated at Kapitthaka. He is considered to be one of the "Nine Jewels" (Navaratnas) of the court of legendary ruler Yashodharman Vikramaditya of Malwa.

Varahamihira's main work is the book Pañcasiddhāntikā (or Pancha-Siddhantika, "[Treatise] on the Five [Astronomical] Canons) dated ca. 575 CE gives us information about older Indian texts which are now lost. The work is a treatise on mathematical astronomy and it summarises five earlier astronomical treatises, namely the Surya Siddhanta, Romaka Siddhanta, Paulisa Siddhanta, Vasishtha Siddhanta and Paitamaha Siddhanta. It is a compendium of Vedanga Jyotisha as well as Hellenistic astronomy (including Greek, Egyptian and Roman elements). Varahamihira was the first one to mention that the ayanamsa, or the shifting of the equinox is 50.32 seconds.

...
Wikipedia