Twenty-eight constellations, also known as "Twenty-Eight Houses" or "Twenty-Eight Stars". In ancient my country, in order to observe the astronomical phenomena and the movement of the sun, moon and five stars, twenty-eight star officials were selected as the symbols for observation, which are called "Twenty-Eight Constellations". It is evenly divided into four groups, each group has seven constellations, which match the four directions of east, west, south and north and the images of animals such as Canglong, white tiger, redbird and Xuanwu (collectively known as turtles and snakes), which are called "four images". The Taoist name is "Four Spirits". The formation of the concept of the Four Symbols in the Twenty-Eight Constellations was very early, and it was already recorded in the early Warring States Period. The later "Book of Rites, Qu Lishang" says: "The red bird is in front of the line and the black dragon is behind, the blue dragon is on the left and the white tiger is on the right." Kong Yingda Shu: "The red bird, black dragon, green dragon and white tiger are the names of the four directions." Weishu of the Han Dynasty " "Shang Shu Kao Ling Yao" says: "The twenty-eight constellations are the vitality of heaven and the essence of all things. Therefore, the seven constellations of Dongjiao, Kang, Di, Fang, Xin, Wei and Ji are shaped like a dragon, which is called 'Zuo Qinglong'. The southern well, The seven constellations of Gui, Liu, Xing, Zhang, Yi and Zhen are shaped like a quail, which is called Qian Zhuque. The seven constellations of Kui, Lou, Wei, Pleiades, Bi, Xi and Shen in the west are shaped like a tiger and are called Right. "White Tiger". The seven constellations of Dou, Niu, Nu, Xu, Wei, Shi and Bi in the north are like turtles and snakes, which is called "Hou Xuanwu". ① Taoism personifies this celestial phenomenon and gives it a name, clothing and color. I am in charge of my duties and worship you. Volume 24 "Twenty-Eight Constellations" of "Yunji Qizhu" says: "A is from the official Yang Shen, and is hosted by the horned star god. There are nine Yang gods. Their surname is Bin and their first name is Yuansheng. They are dressed in green and mysterious single clothes. They are hosted by the horned star. B. The Congguan Yin Shen is also headed by the Kangxing God. There are four Yin Gods. Their surname is Fu and their last name is Sima. They have a horse head and a naked body. They wear red and silk clothes. They carry swords. The rest of the twenty-six constellations are like this. "The Taishang Cave God's Five Stars and Various Constellations of the Sun and the Moon" also describes the appearance and behavior of the twenty-eight constellations. Said: "The essence of the horned star often travels to temples on the Yinmao day after the beginning of spring. It looks like a young man with a small beard, and attends Zen rituals...or wanders to wine shops and drinks by himself...those who know it ask for it, and it can be used to show people how to maintain health and sow seeds." "The spirits of Kang, Di, and Fang often walk together on the Yin Mao Sun, dressed in green clothes... and wander among people or in large gatherings... just to seek for them, and to save the world with others. technique". ③The rest of the twenty-four constellations are similar