Aryabhata is widely regarded as the father of Indian astronomy due to his groundbreaking work in the 5th century CE.

Aryabhata was the first astronomer to propose the heliocentric model, where the Earth revolves around the Sun.

Aryabhata accurately calculated the circumference of the Earth to be 4967 miles, which is remarkably close to the modern value.

Brahmagupta is credited with developing the concept of zero and the decimal system, which revolutionized mathematics.

Varahamihira wrote the 'Surya Siddhanta', which became a standard reference for astronomy and astrology in India.

Varahamihira invented the astrolabe, which was widely used for astronomical observations.

Bhaskara II made significant contributions to trigonometry, including the development of trigonometric formulas and identities.

Bhaskara II wrote 'Lilavati', which became a standard textbook for mathematics and astronomy.

Aryabhata introduced the concept of the 'sidereal year', which is the time it takes for the Earth to complete one orbit around the Sun relative to the fixed stars.

Brahmagupta developed the 'chakravala' method, which is an iterative algorithm for solving indeterminate equations.

Varahamihira wrote the 'Panchasiddhantika', which compared and analyzed five different astronomical systems.

Brahmagupta developed the 'kuttakara' method, which is an algorithm for solving linear equations.

Varahamihira wrote the 'Brihat Samhita', which covered a wide range of topics, including astronomy, astrology, and architecture.

Brahmagupta developed the 'ardharatrika' method, which is an algorithm for calculating the time of sunrise and sunset.