Why should we establish an accurate timing system through systematic astronomical observation?

With the development of agriculture, the division of seasons becomes more and more important, so it is necessary to establish an accurate timing system through systematic astronomical observation. Therefore, astronomical observation has two purposes: timing and predicting the future world. Sumerians divided the trajectory of the sun in the sky into 12 palaces, and the constellation of each palace was named after a mythical god or animal. Their astronomy laid the foundation for today's cosmic timing system, and the division and naming of the stars have always been the same. They formulated the lunar calendar around 4700 BC, about 500 years earlier than the earliest calendar in Egypt. The lunar calendar is divided into 1 year and1February, with 30 days in each month, and the time difference is added. Sumerians also invented the sundial during astronomical observation, and timed it with a water clock.