Some of his jobs were chief astronomer of the Imperial Chancellery for Astronomical and Calendrical Science, and chief minister under the rule of Moana. He also wrote many works ranging from poetry to books full of his scientific research. One was his book of astronomical research and it described his theories about previously unexplained things that could be seen in the night sky. Some things it theorized were that the Moon was lit by the Sun instead of making its own light. It also proposed that the Moon could be eclipsed by the shadow of the Earth. 