The Surya Siddhanta, an ancient Indian astronomical text, contains detailed observations and calculations related to the sun's movement, eclipses, and its influence on agriculture.

Makar Sankranti marks the transition from winter to spring and is considered an auspicious time for sowing crops in many parts of India.

Aryabhata, a renowned Indian astronomer and mathematician, proposed a heliocentric model in the 5th century, where the Earth rotates on its axis and revolves around the sun.

The Panchang is an almanac that provides information about astrological and astronomical events. Farmers use it to determine favorable dates for planting, harvesting, and other agricultural activities.

The Brihat Samhita, written by Varahamihira, contains extensive discussions on the sun's influence on agriculture, including the significance of solstices, equinoxes, and planetary positions.

Ancient Indian astronomers observed the sun's position throughout the year and calculated the time it took for the sun to complete one cycle of seasons, which is approximately 365.242 days.

Crop rotation is an ancient Indian agricultural practice where farmers grow different crops in a sequence on the same land to maintain soil fertility, control pests, and improve overall crop yield.

The Solstice Points mark the sun's highest and lowest positions in the sky during the year, which are significant for determining the seasons and agricultural activities.

The Gnomon, a simple yet effective instrument, was used in ancient India to measure the sun's altitude and determine the time of day by observing the length of its shadow.

Pongal is a harvest festival celebrated in South India to express gratitude for a bountiful harvest and pray for continued prosperity in agriculture.

Ancient Indian astronomers calculated the duration of a solar eclipse by observing the time taken for the moon to pass through the Earth's shadow.

Contour farming is an ancient Indian agricultural practice where crops are planted in rows or ridges along the contours of the land, helping to conserve soil and water, and prevent erosion.

The Equinox Points mark the days when the sun is directly above the Earth's equator, resulting in equal lengths of day and night.

The Krishi-Parashara is an ancient Indian agricultural text that offers comprehensive guidance on crop selection, soil preparation, irrigation techniques, and various agricultural practices.