Which dynasty divided the year into 65438+February; When were the 24 solar terms measured?

In the early years of the Western Han Dynasty, the Zhuan Xu calendar of the Qin Dynasty was followed. However, there are some mistakes in Zhuan Xu Calendar. BC 104 (the sixth year of Yuanfeng), at the suggestion of Sima Qian and others, Emperor Wu of the Han Dynasty ordered the calendar to be changed. In BC 104, astronomers such as Luo He made a calendar. Taichu calendar stipulates that a year is equal to 365.2502 days and January is equal to 29.5086 days. Change October as the beginning of the year to the first month of the year; Beginning to adopt twenty-four solar terms that are beneficial to agricultural time; Take the month without neutral gas as leap month to adjust the contradiction between the sun and the lunar calendar. This is an epoch-making progress in the history of China. Taichu calendar method also drew a solar eclipse cycle of 135 months based on astronomical observations and years of records by historians. Taichu calendar is not only the first relatively complete calendar in China, but also the most advanced calendar in the world at that time. It has been running for 189 years since it came out.