What is the historical story of Li, a great astronomer in the early Tang Dynasty?

It should also be mentioned that Li was a great astronomer in the early Tang Dynasty and a divination master trusted by Emperor Taizong at that time. He wrote an astrological work, Yisizhan, and a famous book in the history of astronomy, The Book of Jin? Tian. It is said that he "every good or bad luck, if combined, then artists suspected that he had other services, not because of learning, but not because of quantity" ("Old Tang Book? Biography of Li. He even used his clever words and excuses to dissuade Emperor Taizong from a rumored activity of cleaning the so-called "female warrior king" (alluding to Wu Zetian). Li's achievements show that astronomy and astrology went hand in hand in the Tang Dynasty.