What are the contributions of Li Chunfeng, an astrologer in the Tang Dynasty?

What are the contributions of Li Chunfeng, an astrologer in the Tang Dynasty?

Li Chunfeng, a native of Qizhou in the early Tang Dynasty (now Fengxiang, Shaanxi), a famous astronomer and mathematician. His father Li Bo was Gao Tangwei of the Sui Dynasty, and later became a monk. He was named Huang Guanzi and the author of "Astronomical Elephant Fu". In his early years, Li Chunfeng studied Taoism in Tiantai Mountain and was familiar with astronomy and astrology. At the beginning of the Tang Dynasty, he pointed out the error of "Wuyin Yuanli", and later switched to Li Chunfeng's "Lindeli". According to historical records, Li Chunfeng had successfully predicted a solar eclipse.

Li Chunfeng used to work as a secret nurse, edited "Jiazi Yuanli", and authored seven volumes of "Faxiangzhi". His theory of "the difference between the gains and losses of the previous armillary sphere" has a significant impact on later generations. He was the first person in the world to rank wind power. In his meteorological work "Osi Zhan", he classified wind into 8 levels. It was only a thousand years later that British scholars classified the wind force into levels 0 to 12.

The famous prophecy book "Tui Bei Tu" in history is said to have been made by him and Yuan Tiangang, sitting opposite each other, and guessing what they did in the past and the present.