How did the twenty-four solar terms come into being?

24 solar terms was born more than 3000 years ago, which is related to the sun. After years of observation, the ancients found that the sun shadow is the longest on a day in the twelfth lunar month and the shortest on a day in June every year. The longest day of the sun shadow is called the solstice, which is the winter solstice in the 24 solar terms; The shortest day is called the shortest day, which is the summer solstice.

The longest day of the sun shadow is called the solstice, which is the winter solstice in the 24 solar terms; The shortest day is called the shortest day, which is the summer solstice. Later, on this basis, people discovered the vernal equinox and the autumn equinox.

In this way, people first identified four solar terms.

Another explanation:

The twenty-four solar terms were formulated by the ancients according to the ecliptic plane, which reflected the influence of the sun on the earth and belonged to the solar calendar category. It is an important part of the long history and culture of the Chinese nation and embodies the historical and cultural essence of Chinese civilization. Twenty-four solar terms were established in ancient times, and were absorbed into taichu calendar law in Han Dynasty as a supplementary calendar to guide farming.

Twenty-four solar terms are not only the time criterion promulgated by successive governments, but also the compass to guide agricultural production and to predict cold, warm, snow and rainy days in people's daily life.

24 solar terms was born more than 3000 years ago, which is related to the sun. After years of observation, the ancients found that the sun shadow is the longest on a day in the twelfth lunar month and the shortest on a day in June every year. The longest day of the sun shadow is called the solstice, which is the winter solstice in the 24 solar terms; The shortest day is called the shortest day, which is the summer solstice.

Later, on this basis, people discovered the vernal equinox and the autumn equinox. In this way, people first identified four solar terms.