What does the vernal equinox mean?

Vernal equinox: "Divider, the point where Huangchi meets, the sun comes here, and the day and night are equally divided."

The significance of the vernal equinox, first, refers to the equal division of day and night, each of which is 12 hours; Second, in ancient times, it was spring from beginning of spring to long summer, and the vernal equinox happened to be in the three months of spring, and spring was equally divided.

2. Autumnal equinox: "The autumnal equinox is half cloudy and half sunny, so it is cold day and night and it is flat in summer." The autumnal equinox means "half" ?

"vernal equinox" has two meanings:?

First, on this day, the sun reaches 180 degrees and points directly at the equator of the earth, so the 24 hours of this day are divided equally, each with 12 hours; There is no extreme day and night phenomenon in the world. ?

Secondly, according to the method of seasonal division in ancient China, which took beginning of spring, Changxia, beginning of autumn and beginning of winter as four seasons, the autumnal equinox lived in autumn for 90 days and divided the autumn equally.

3. Summer solstice: "The day reaches the north, the day is long and the shadow is short, so it is called summer solstice. At best, it is excellent. "

On the day of summer solstice, the sun directly reaches the northernmost part of the year, almost directly to the Tropic of Cancer (23 26' north latitude), and the daytime in the northern hemisphere reaches the longest, and the farther north it is, the longer it is. ?

4. Winter solstice: When the cathode arrives, the yang begins to grow, the sun faces south, the day is short and the shadow is long, so it is called "winter solstice".

This day is the shortest day and the longest night in the northern hemisphere all year round.

Expand knowledge:

The 24 solar terms are: beginning of spring, Rain, Sting, Equinox, Qingming, Grain Rain, Changxia, Xiaoman, Mangzhong, Summer Solstice, Xiaoxia, Daxia, beginning of autumn, Chushu, Bailu, Autumn Equinox, Cold Dew, First Frost, beginning of winter, Light Snow, Heavy Snow, Winter Solstice, Slight Cold and Severe Cold. ?

The twenty-four solar terms of the lunar calendar is a supplementary calendar for guiding farming in ancient China, and it is the crystallization of long-term experience and wisdom of working people in ancient China. ?

As early as the Spring and Autumn Period, the ancient sages of China set four solar terms, namely midsummer, midsummer, midsummer and winter solstice, and constantly improved and perfected them. By the Qin and Han Dynasties, the 24 solar terms had been completely established.

The intangible cultural heritage of the twenty-four solar terms of the lunar calendar is very rich, including related proverbs, ballads and legends, traditional production tools, household appliances, handicrafts, calligraphy and painting, and China festival culture, production ceremonies and folk customs closely related to the festival.

Twenty-four solar terms are the concrete expression of ancient agricultural civilization in China, which has high research value of agricultural history and culture.

On May 20th, 2006, with the approval of the State Council, the 24 solar terms declared by china agricultural museum were included in the first batch of national intangible cultural heritage list.

Reference link: Twenty-four solar terms of China Popular Science Network.