The origin of 28 stars?

Twenty-eight constellations first sprouted in Xia and Shang Dynasties, and further developed in the Spring and Autumn Period and the Warring States Period, which were recorded in Shangshu and Zuoshi Chunqiu. The early 28 constellations were mainly used to observe astronomy and meteorology, which was of great help to agriculture at that time, and could also be used as the current calendar by dividing the seasons at that time. The earliest record of the western calendar was in the Babylonian period. We can see the ancient people's division of a week from the following poem:1April 6, 2003, the room was full of vitality, and in the afternoon, the woman was in danger, her stomach was full, and the ghost Liu Yi was involved in the well. Therefore, the so-called 28 stars are just ancient calendars. In Songshan, there is the earliest observatory in China, the Stargazing Observatory, which was built in the early Yuan Dynasty. Guo Shoujing once re-observed the positions of 28 stars and other constant stars here, and compiled the most advanced calendar at that time-service calendar. The rise of Taoism is a turning point in astrology. Taoism has a new interpretation of 28 stars. They think that the twenty-eight stars are the gods who protect the four beasts, and the four gods are the gods who protect heaven and earth. So there are the so-called four gods. They think that Suzaku represents the sky, so it is supreme; Qinglong and Baihu are symbols of power and prestige, and Xuanwu is the most special. According to legend, Xuanwu is the youngest and weirdest of the nine sons of the Yellow Emperor, because it is like a tortoise and snake, but it can live for tens of thousands of years. From the present point of view, it is just a turtle, so Xuanwu stands for longevity. Taoism also arranges many maps according to the directions of the four gods and twenty-eight stars, such as the "Nine Curves Yellow River Array" and so on. Later, these evolved into feng shui.