The reasons for China's outstanding achievements in ancient astronomy

The outstanding achievements of ancient astronomy in China are mainly due to the needs of agricultural development.

Agricultural production is closely related to seasons and astronomical phenomena. The knowledge of ancient astronomical calendars in China was accumulated in the practice of agricultural production, which directly served agricultural production.

The ancient calendar of China adopted the combination of Yin and Yang, that is, the cycle of the sun was taken as the year, the cycle of the moon as the month, and the leap month was used to coordinate the relationship between the year and the month.

According to the position change of the sun in a year and the evolution order of the ground climate caused by it, the ancients divided the year into 24 segments and 12 months to reflect the four seasons, temperature and phenology.

These 24 solar terms, established by the movement of the sun, reflect the changes of the four seasons and are closely related to the production of agriculture and animal husbandry, so they are also called lunar calendar.

The complete name of the twenty-four solar terms first appeared in Huai Nan Zi Tian Wenxun in the early Han Dynasty, which is consistent with the current name. Solar terms originated in ancient China, reflecting the changes of the four seasons when the earth revolves around the sun, and reflecting the farming season, which is well-known in rural areas. With the spread of the ancient calendar in China, solar terms spread to the places where overseas Chinese went. Solar terms are determined according to the apparent position of the sun in the starry sky. Solar terms are also called twenty-four solar terms, which are the floorboard of twelve kinds of Chinese gas and twelve solar terms alternately arranged.