Varahamihira lived in Ujjain and was one of the nine jewels (Navaratnas) of the court of Chandragupta II. He wrote Panchasiddhantaka, the five treatises on astronomy (NOT astrology). It summarises five earlier astronomical treatises, namely the Surya Siddhanta, Romaka Siddhanta, Paulisa Siddhanta, Vasishtha Siddhanta and Paitamaha Siddhantas.
About Surya Siddhanta
In India, people had started the use of the astronomical instruments before 1000 BC. During this period one of the prominent books ‘Suryasidhanta’ was written for astronomical calculations. There are several works with the same name, BUT the Original writer of Surya Siddhanta is UNKNOWN.
The title ‘Suryasidhanta’ means sun theory and it highlights the calculations of positions of stars and planets. Some of the Indian mathematicians later have developed their own instruments and developed their own methods to facilitate the theory of ‘Suryasidhanta’. Introduction of zero in mathematics and the decimal method of calculation is one of such invaluable contribution. We should note that Varahamihira had contrasted Surya Siddhanta along with his 4 other treatises in the panchsiddhantika viz. Paitamaha Siddhantas, Paulisha , Romaka Siddhantas and Vasishta Siddhanta. Citation of the Surya Siddhanta is also found in the works of Aryabhata.
Varahamihira has done a valuable job of compilation of five astronomical theories, which were in use before Crist, and suryasidhanta is one of them. This compiled book is known as ‘Panchasidhanta’. He had developed some ring and string instruments.