How many months were there in the Han Dynasty? 10 is a year? What month is the first month?

The average year is 12 months, and the leap year is 13 months. In the early Han Dynasty, October was the beginning of a year, and later it was changed to the first month (silver moon, the first month of the lunar calendar). The layman once heard that there were two different concepts of age in ancient times. The year belongs to the lunar calendar and the year belongs to the solar calendar, and the length is determined by the sun. It can be seen that age belongs to different concepts, the length of a year is changing, and the length of a year is relatively stable. The following 365.2502 days should refer to a year's time, which may be called the length of a year. ) The detailed explanation is as follows:

1. 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.

2. A Journey to the Beginning lasted from May of the first year of the Beginning to February of the second year of Emperor Hanyuan and Jiayin, totaling 1.89 years. It is the first existing ancient calendar with relatively complete documents and records in China. At the same time, it takes into account the laws of the apparent motion of the sun and the changes of the moon's profit and loss, and adopts the average value of the tropic year and the first month of the lunar calendar as the basic cycle, which belongs to the Yin-Yang calendar and inherits the scientificity and rationality of the ancient Chinese Yin-Yang calendar. The adoption of Xia Zheng-taking silver moon as the beginning of the year, keeping pace with the farming rhythm of spring planting, summer busy, autumn harvest and winter leisure, has brought great convenience to guide the production and life of agriculture and animal husbandry. Taichu calendar also takes the months without neutral atmosphere (even numbers in the 24 solar terms, namely, winter solstice, severe cold, fright, vernal equinox, Qingming, Xiaoman, summer solstice, generals' mansion, hell, autumn equinox and light snow at the beginning of frost) as leap months, which is more reasonable than the previous year-end leap method.

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