5 Siddhantas Astronomical knowledge was very well developed during the Vedic and Vedang periods and was further developed and updated in subsequent periods. सिद्धान्त is one of the sub-branches of Ganit Skandha. For various branches of Astronomy see https://intrestingcosmos.blogspot.com/2024/03/ -of 01 March 2024 Knowledge of the position of the Sun, Moon, and other planets was required for calendrical, religious, and daily rituals. The history of astronomical works can be assessed from the oldest known group of 5 ancient सिद्धान्त known as पंचसिद्धांतिका written by Varahmihira (500 CE) These 5 सिद्धान्त are पितमहः, वसिष्ठ, रोमक, पौलिश , सौर Varahmihira in his पंचसिद्धांतिका says that the सिद्धान्त written by Paulisa is fairly accurate, but not as accurate as Saura/Surya Siddhant. The accuracy of others is doubtful. These Siddhantas outline methods for calculating the me...