What are the 24 solar terms?

Beginning of spring, Rain, Creeping, Vernal Equinox, Qingming, Grain Rain, Changxia, Xiaoman, Mangzhong, Summer Solstice, Xiaoshu, Dashu, beginning of autumn, Chushu, Bailu, Autumnal Equinox, Cold Dew, Chufrost, beginning of winter, Light Snow, Heavy Snow, Winter Solstice, Slight Cold and Severe Cold.

Twenty-four solar terms refer to the special festivals in the dry calendar that indicate the season, phenology, climate change and the establishment of "December construction". "Twenty-four solar terms" was originally set by Beidou bucket handle.

The "twenty-four solar terms" are divided by the method of "constant gas", that is, each solar term corresponds to a certain position that the earth reaches every time it runs 15 on the ecliptic; It divides the sun's annual trajectory into 24 equal parts, each 15 is an equal part, and each equal part is a solar term, starting in beginning of spring and ending in severe cold.

Extended data

origin

In ancient China, the sundial was measured by earth gauge, and the longest sundial was defined as "solstice" (also called solstice, that is, the lunar calendar, solstice and winter solstice of the four images in Taiji diagram), and the shortest sundial was "solstice" (also called short solstice and summer solstice). In spring and autumn, one day the length of day and night is the same, which is called "vernal equinox" and "autumn equinox", and there are many people of all ethnic groups.

There were only four solar terms (four images, namely four seasons) in Shang Dynasty, and it developed to eight (eight diagrams) in Zhou Dynasty, and 24 solar terms were completely established in Qin and Han Dynasties [3]. In BC 104, the taichu calendar written by Deng Ping officially set 24 solar terms in the calendar, and defined the astronomical position of the 24 solar terms.

The names of the twenty-four solar terms first appeared in Tian Zi Xun in Huainan, and the concepts of Yin and Yang (the movement of the sun and the moon), four seasons (the four seasons), eight places (the gossip), twelve degrees (the hour) and twenty-four solar terms were also mentioned in the preface to Historical Records Taishi Gong. During the period of Emperor Wu of the Han Dynasty, Luo compiled solar terms into the calendar, stipulating that the month without neutral gas was the last month of leap month.

Each of the 24 solar terms corresponds to the position where the sun reaches every movement 15 on the ecliptic. The twenty-four solar terms are divided into 12 solar terms and 12 solar terms, which correspond to each other one by one. The twenty-four solar terms reflect the annual visual movement of the sun, so its Gregorian calendar date is almost fixed. The solar term in the first half of the year is on the 6th, the solar term in the second half is on the 8th, and the solar term is on the 23rd, with a difference of 1 ~ 2 days.

The naming of the 24 solar terms reflects the changes of seasons and climate. Beginning of spring, Spring Equinox, Long Summer, Summer Solstice, beginning of autumn, Autumn Equinox, beginning of winter and Winter Solstice, also known as Eight Places, are eight key nodes to distinguish the influence of revolutionary movements on the earth. Sixteen items, such as rain, thorn, Qingming, Grain Rain, Xiaoman, awn seed, slight summer heat, great summer heat, early summer heat, white dew, cold dew, early frost, light snow, slight cold and severe cold, reflect the subtle climate changes in the four seasons.

Baidu encyclopedia-24 solar terms