Who is the founder of the 24 solar terms table?

Twenty-four solar terms were first seen in Liu An's "Huainan Tian Zi Xun" in the Western Han Dynasty.

In BC 104, taichu calendar, edited by Luo Xiahong and Deng, officially set up 24 solar terms in the calendar, defined the astronomical position of the 24 solar terms, and stipulated that the month without neutral gas was designated as the leap month of last month.

Twenty-four solar terms originated in the Yellow River Basin. Since 2000, the main political centers in China have been concentrated in the Yellow River Basin, and the 24 solar terms have been established on the basis of climate and phenology in this area. Because China has a vast territory and changeable terrain, the 24 solar terms are only a reference for many regions.

As early as the Spring and Autumn Period and the Warring States Period, the sundial was measured by earth gauge in ancient China (that is, a pole was erected on the plane to measure the length of the shadow of the noon sun) to determine the four solar terms of midsummer, midsummer, midsummer and winter solstice.

In a year, the shortest day of the noon shadow is the summer solstice, the longest day is the winter solstice, and the moderate shadow length is the vernal equinox or autumnal equinox. The Book of History in the Spring and Autumn Period recorded the solar terms. There were only four solar terms in Shang dynasty, while there were eight solar terms in Zhou dynasty.