In some ancient books, the seven stars are not mentioned, but the nine planets of the Big Dipper. Where did the extra two stars come from? It turned out that the ancients thought that Beidou was actually nine planets, but it was actually just "seven now and two hidden", that is, seven stars could be seen, while the other two were hidden. Compared with people, it corresponds to nine tricks. We generally know the seven orifices, that is, eyes, ears, nostrils and mouth, and the other "two hidden orifices" are urethra and anus. The so-called "nine know nothing" means that after death, these nine know nothing. Because the nine planets of Beidou correspond to the nine strokes of human beings, people say that Beidou is dead. In Romance of the Three Kingdoms, Zhao Yan borrowed a passage from Guan Ju: "Beidou pays attention to death, while Nan Dou pays attention to life. Now that my life has added another stroke, what else is there to worry about? " The Big Dipper has a name. They are: Shu Tianxing, Tian Xuanxing, Tianjing Star, Tianquan Star, Yuxing Star, Luyang Star, Yaoguang Star, Cave Star and Hidden Star. These names are still used in today's astronomy books, while another group of old names only exist in ancient books: Yang Xing, Taiwei of Heaven, and Director of Political Affairs; Yin essence star, slaughter above the sky, theme; The real star, the sky is mediocre, the main fairy; Xuanxing, the guerrilla in the sky, the main attack; Tian Wang Dan Yuanxing, the master of life; Polaris, the sky is too normal, the main rise; Guan Xing, the god in heaven, is the master of heaven and earth. Auxiliary star, the star of Buddha, the star of Jade Emperor; Bixing, too often true star. The two hidden stars in the nine planets of Beidou, Fuxing and Bixing, are rich and profitable in astrology, geomantic omen and transportation. Because it is a hidden star, according to scientific vocabulary, it is invisible to the naked eye. So if anyone can really see it, it will be a fortune, and it will be a fortune in the future. "Cloud Seven Signs, Volume 24, the Sun, the Moon and the Stars" records: "The nine emperors and nine ladies of the son of heaven are anonymous and know that they have extended their lives for thousands of years. I usually look at it in the evening. I want to see the portrait of Mrs. Huang Jun, remember her surname, and I have a heart. I can see the eighth and eighth planets and prolong my life. "