Guo Shoujing was a major influence in the development of science in China. The tools he invented for astronomy allowed him to calculate an accurate length for the year, which allowed Chinese culture to set up a whole new system of exact dates and times, allowing for increasingly accurate recording of history and a sense of continuity throughout the country. The calendar stabilized the Chinese culture allowing subsequent dynasties to rule more effectively. Through his work in astronomy, he was also able to more accurately establish the location of celestial bodies and the angles of the Sun relative to Earth. He invented a tool which could be used as an astrological compass, helping people find north using the stars instead of magnets.