How are the 24 solar terms arranged?

The ancients used the lunar calendar according to the cycle of the moon, but many places in daily production and life need to do things according to the cycle of the sun, the most typical of which is agriculture. Spring ploughing, autumn harvest and winter storage should be guided by the movement of the sun (in fact, of course, the earth revolves around the sun), so the clever ancestors invented a complicated calculation method to describe the movement of the sun, that is, the 24 solar terms. The twenty-four solar terms were formulated by our ancestors according to the lunar calendar. But it is so consistent with the modern Gregorian calendar, which shows that our ancestors not only understood the laws of motion of the moon and the sun, but also mastered the relationship between them. Of course, the 24 solar terms reflect the climate change in the Huanghuai Valley of China, and other regions should increase or decrease according to their geographical location.

As for the calculation method, I'll give you an excerpt from the Internet:

The time when the sun runs along the longitude of the Yellow River from zero 15 degrees is called "a solar term". It runs 360 degrees every year, and * * * experiences 24 solar terms, twice a month. Among them, the first solar term of each month is "solar term", that is, beginning of spring, Jingzhe, Qingming, Changxia, Mangzhong, Xiaoshu, beginning of autumn, Bailu, Hanlu, beginning of winter, Heavy Snow, Xiaohan, etc. 12 solar terms; The second solar term of each month is "Zhongqi", that is, there are 12 solar terms such as rain, vernal equinox, Grain Rain, Xiaoman, summer solstice, great heat, intense heat, autumnal equinox, first frost, light snow, winter solstice and great cold. "Solar term" and "neutral qi" appear alternately, each lasting 15 days. Now people have called "solar terms" and "neutral gas" solar terms.

Twenty-four solar terms reflect the apparent movement of the sun in one year, so the dates of solar terms are basically fixed in the current Gregorian calendar, with the first half of the year being 6 days and 2 1, and the second half being 8 days and 23 days, with a difference of 1 ~ 2 days.