Related article: Zodiac is like a Balance with Chithira Vishu on top of the central beam
1. As the Earth rotates on its 23.5 degree tilted axis from west to east, it would appear that celestial bodies that rise in the eastern horizon set in the western horizon, except for the stars closer to the celestial North (South) Pole that would appear to circle it.
Aryabhata and Bhaskara II had estimated the tropical year at 365 days, 6 hours, 12 minutes, and 30 seconds, the same figure as estimated in the ancient Indian text, Surya Siddhanta. The modern figure for the tropical year is approximately 365 days, 5 hours, 48 minutes and 45 seconds.