Varahamihira, a renowned Indian astronomer and astrologer, is credited with developing the concept of the zodiac and the system of 12 zodiac signs in his work, the Brihat Samhita.

Indian astronomers employed trigonometry, particularly the sine and cosine functions, to determine the positions of celestial bodies and solve astronomical problems.

Aryabhata proposed the Epicyclic Model, which combined circular motions to explain the movement of planets around the Sun.

Aryabhata made significant contributions to mathematics, including the development of the concept of zero and the introduction of the decimal system.

Indian astronomers invented the Astrolabe, a versatile instrument used to measure the altitude of celestial bodies and solve various astronomical problems.

Brahmagupta was the first astronomer to propose the concept of the precession of the equinoxes, the gradual shift in the position of the equinoxes over time.

Indian astronomers used interpolation, a mathematical technique, to estimate the time of eclipses based on past observations and data.

Aryabhata made significant contributions to trigonometry, including the development of the sine function and the introduction of trigonometric tables.

Varahamihira's Brihat Samhita is a comprehensive astronomical treatise that encompasses astrology, astronomy, and mathematics.

Brahmagupta made significant contributions to astronomy, including the development of the concept of the mean motion of the planets and the introduction of the true anomaly.

Aryabhata's Surya Siddhanta is a renowned astronomical treatise that covers topics such as astronomy, mathematics, and astrology.

Brahmagupta made significant contributions to astronomy, including the development of the concept of the apogee and the perigee of the Moon.

Bhaskara II's Siddhanta Shiromani is a comprehensive astronomical treatise that encompasses astronomy, mathematics, and astrology.

Brahmagupta made significant contributions to astronomy, including the development of the concept of the ecliptic and the introduction of the concept of the nodes of the Moon.

Varahamihira's Brihat Samhita is a comprehensive astronomical treatise that encompasses astrology, astronomy, and mathematics.