What calendar is the taichu calendar method based on?

Taichu calendar is based on the summer calendar.

Taichu calendar divides a day into eighty-one years, so it is also called "eighty-one calendar". It is a relatively complete calendar in ancient China and an epoch-making progress of our calendar. In the early Han Dynasty, we inherited the Qin system, followed the ancient calendar Zhuan Xu Calendar, and made a comprehensive comparison between taichu calendar and Zhuan Xu Calendar, which made great progress.

However, the early calendar also has some shortcomings. Its data of 8 1 minute is the self-multiplication of Huang Zhongmi's nine-inch data, and the calendar starts with rhythm, which lacks scientific basis. According to the law, the year of return is one year and the new moon is January. Taichu calendar reverted from October in winter to the first month of the summer calendar, and absorbed the 24 solar terms of the dry calendar as an auxiliary calendar to guide farming, and took the month without neutral atmosphere as a leap month, making the calendar more suitable for farming.

The Origin of taichu calendar Law

Taichu calendar, founded in the Western Han Dynasty, was the first complete calendar in China and the most advanced calendar in the world at that time. In the sixth year of Yuanfeng (BC 104), at the suggestion of Sima Qian and others, Emperor Wu of the Han Dynasty ordered the calendar to be changed, and the Zhuan Xu calendar with large errors was changed to taichu calendar. Taichu calendar was formulated by astronomers Luo, Li, Li and others. This calendar stipulates that a year is 365.2502 days, and January is 29.53086 days, changing the original early October to the first month.

Taichu calendar adopts the solar terms which are beneficial to agricultural production in 24 solar terms, and takes the months without neutrality (continuous rain, vernal equinox, Grain Rain and other solar terms). ) is a leap month, thus adjusting the contradiction between the sun's Sunday and the lunar calendar. According to years of astronomical observation and the records of historians, the solar eclipse cycle is calculated as 135 months.