Vernal equinox

Vernal equinox

Equinox is the fourth of the 24 solar terms, which is an important season for farming. The sun is directly on the earth's equator, and day and night are almost equal. In ancient times, spring was from the beginning of spring to the beginning of summer, and the equinox was in the middle of the three months of spring. The sun reaches 0 degrees of the Yellow longitude, and it meets on March 19-22 of the Gregorian calendar every year. "The equinox is half of yin and Yang. Therefore, day and night are both cold and hot. It is recorded in the lunar calendar that "Dou Zhi Ren is the vernal equinox, which goes around the Zhou Tian. The day and night of the northern and southern hemispheres are equally divided, and it is also half of the spring, so it is called the vernal equinox." From this day on, the position of direct sunlight gradually moves northward, and the length of day and night in the northern and southern hemispheres also changes. The length of day and night in the northern hemisphere is longer than that in the southern hemisphere.

As soon as the vernal equinox arrives, the rainfall increases significantly, and the average ground temperature in China has stabilized through 10 degrees, which is the spring temperature defined by climatology. After the vernal equinox, the climate is mild, the rain is abundant, and the sun is bright. The overwintering crops in most parts of China enter the spring growth stage, which is also the sowing time of early rice.

The equinox has three periods: "one is the arrival of Xuanniao, the second is the sound of thunder, and the third is the beginning of electricity.". It is also one of the spring equinox customs to send a picture of a spring bull. In addition, the vernal equinox customs such as offering sacrifices to 100 birds and sticking sparrow beaks also bear people's expectations for the farming season.

historical origin

The origin of the name

Before and after March 21 of the solar calendar, the sun reaches 0 degree of the Yellow longitude, which is the vernal equinox of the 24 solar terms. The equinox is the half of spring, so it is called equinox. On the Equinox Day, the sun is directly above the equator, and the duration of day and night is almost equal, 12 hours each. After the vernal equinox, the position of the sun gradually moves north, and the days begin to lengthen and the nights begin to shorten. Therefore, the equinox in ancient times was also known as "sun", "day and night equinox", "mid Spring Moon". "Yueling 72 Hou Ji Jie" also records: "in February, the half is also divided, this is the half of 90 days, so it is called the division." Another "spring and autumn fan Lu · Yin and Yang in and out of the first and second chapters" said: "the equinox, yin and Yang phase half also, so day and night are cold and summer flat." In addition, the first calendar of the Ming Dynasty says, "the point where the yellow and red intersect is the equinox of the day and the night when the sun moves here." Therefore, the meaning of the equinox has two aspects: one is to divide the day and night equally; the other is to divide the spring equally from the beginning of spring to the beginning of summer in ancient times. In ancient China, the vernal equinox was divided into three periods: "at the beginning, Xuanniao arrives; at the second, thunder makes sound; at the third, electricity begins."

Zhouyue in yizhoushu: "Zhongqi in spring and March: Jingzhe, vernal equinox, Qingming."

In the book "Zhenze Changyu · Xiangwei" written by Wang Wei of the Ming Dynasty, "the second festival is a time when Yang Qi rises for a total of 42000 Li, which is in the middle of heaven and earth and the festival of the vernal equinox."

It is also recorded in the ancient Chinese calendar that "three days before the equinox, the sun enters the equator.".

Astronomical calendar

Astronomical phenomena

The vernal equinox refers to the position of the sun between 0 ° and 15 ° of the Yellow longitude in the time cycle, which is from March 20 to April 5. But in practice, it usually refers to the day when the sun is really at 0 ° of the Yellow longitude: March 20 or March 21. 　

Phenomena on earth

At the vernal equinox, the point of direct sunlight is on the equator. After that, the point of direct sunlight continues to move northward, so the vernal equinox is also called ascending equinox.

At the equinox, in theory, the world's day and night are equal (see Twilight). After the vernal equinox, the days are getting longer and the nights are getting shorter in the northern hemisphere, and the nights are getting longer and the days are getting shorter in the southern hemisphere. 　

At the vernal equinox, there is no polar day or night in the world. After the vernal equinox, the polar day begins near the north pole, and the range gradually increases; the polar day ends near the south pole, and the polar night begins, and the range gradually increases.

Climate change

At the equinox, China enters a beautiful spring except for the Qinghai Tibet Plateau, Northeast China, Northwest China and northern North China. The daily average temperature in all parts of China has steadily increased to above 0 ℃ except for the alpine mountainous areas where winter occurs all year round and the areas north of 45 ° n.

At this time, the severe cold has passed away, and the temperature rises rapidly, especially in North China and the Huang Huai plain. The daily average temperature almost rises to more than 10 ℃ at the same time with the rainy areas along the Yangtze River and the south of the Yangtze River, and enters the beautiful spring. On the vast land, the shore is green with willows, the warbler flies, the grass grows, the wheat is jointing, the rape is fragrant, the peach is red, the plum is white, the spring is yellow, and South China is a late spring scene.

From the perspective of climate law, the precipitation in the south of the Yangtze River increased rapidly and entered the "peach blossom flood" period in spring; in the vast areas of northeast, North and Northwest China, where "spring rain is as expensive as oil", the precipitation is still very little, and resisting the threat of spring drought is the main problem in agricultural production.

Phenological phenomenon

Xuanniaozhi: xuanniaozhi, yanye, Gaoyou said: "spring equinox comes, autumn equinox goes."

Thunder is phonation: Yin and yang are thin, which is called thunder. At this point, the four Yang are gradually flourishing, and Yin Yan is still there, so the thin phase is phonation. Yunhui says, "it's difficult for Xiang Qi to come out." Annotation said: "hair, still out."

The first electricity: electricity, the sun also; four Yang Sheng long, the value of gas vent when light Yan. Therefore, "Li Jie" said: "every sound is Yang; light is Yang. The book of changes says: "thunder and lightning are combined into chapters." "Gongyang Zhuan" also said: "electricity, thunder." Yes, Xu said, "Lei Yang, Dian Yin." No. When there is no thunder in midsummer, there is also electricity.

Farming activities

As the saying goes: "spring equinox wheat up, fertilizer and water to follow.". A spring rain, a warm, after the spring rain busy farming. The busy spring season is about to begin. Spring management, spring farming and spring planting are about to enter a busy stage. After the vernal equinox, the overwintering crops enter the growth stage, so the field management should be strengthened. Due to the rapid rise of temperature and relatively large water demand, farmers should strengthen water conservation. In the areas with less rain in spring in the north, we should pay close attention to spring irrigation, water saving and fertilizer application, and pay attention to the prevention of late frost damage; in the south, we still need to do a good job in drainage and waterlogging prevention. The work of early rice seedling raising in Jiangnan and film seedling raising in Jianghuai region has begun. The weather changes frequently in early spring. We should pay attention to soaking seeds and accelerating germination when the cold air comes, and sowing when the cold air is over.

In northern China, where spring rain is as expensive as oil, resisting spring drought is still an important agricultural activity during the vernal equinox. In these areas, we should pay close attention to spring irrigation, water saving and fertilizer application, and strengthen the preparation for resisting spring drought and freezing injury.

In spring, when the weather gets warmer, cold air often invades, especially in Jiangnan and along the Yangtze River. The cold air in the north meets the warm and humid air flow from the south, resulting in continuous rain in spring, which significantly reduces the temperature, thus forming the so-called "cold in late spring".

traditional custom

overview

The main customs of vernal equinox include laying eggs, ancestor worship, outing and eating wild vegetables. Equinox is the Chinese lunar term, or the new year of Iran, Turkey, Afghanistan, Uzbekistan and other countries, which has lasted for more than 3000 years. Mexicans and American Indian descendants have inherited the custom of celebrating the equinox. Twenty four solar terms were introduced into Japan more than one thousand years ago. Some solar terms were listed as the legal holidays in Japan. The vernal equinox is a public holiday in contemporary Japan. In the traditional calendar of Vietnam, most of the "24 solar terms" are also preserved.

Standing egg

On the Equinox Day every year, tens of millions of people around the world are doing the experiment of erecting eggs. It is difficult to find out why this "Chinese custom" has become a "world game". But it's easy and fun to play.

Ancestor worship

As early as the Zhou Dynasty, there was the Spring Equinox ceremony. According to the book of rites, the custom of "sacrificing the sun at the altar" has been handed down from generation to generation The Ritan is located in the east of Ritan Road, Southeast of Chaoyang Gate in Beijing. It is also called chaoritan. It is the place where the emperors of Ming and Qing Dynasties sacrificed to Daming God (the sun) on the spring equinox.

Eat spring vegetables

Confucius said: "from time to time, do not eat." Food has its own season. Spring vegetables, as the name suggests, are spring vegetables.

In Lingnan area, spring equinox has the custom of eating spring vegetables. "Chuncai" is a kind of wild amaranth, which is called "chunbihao" by villagers. On that day, the whole village went to pick spring vegetables. When searching in the field, it is usually light green, thin trees, about the length of palm. The spring vegetables are usually boiled with fish fillets at home, which is called spring soup. There is a doggerel: "spring soup perfusion viscera, wash the liver and intestines. The whole family, young and old, is safe and healthy. "

In the past, there was a custom of "eating spring vegetables on the equinox" in the four cities of Lingnan. "Spring vegetable" is a kind of wild amaranth. The spring vegetable picked from the field is generally "rolling soup" with fish fillets, which is called "spring soup". The so-called "spring soup irrigation viscera, wash the liver and intestines.". The whole family is safe and healthy. On this day, women in Yangjiang would go to the mountains to collect leaves of flowers, make them into powder and rice flour, and make noodles in soup. It is said that they can clear heat and detoxify.

Spring cattle

When the equinox arrives, send out the picture of spring cattle. What is the picture of spring bull? The red or yellow paper of Erkai is printed with the solar terms of the lunar calendar, and then printed with the pattern of farmer farming, which is called "the picture of spring cattle". Generally speaking, those who send pictures are good at singing. They mainly talk about spring ploughing and auspiciousness, which is not against the common saying of farming time. Every time they go to a family, they are even more spontaneous, saying that the owner is happy and giving money. Although these words come out casually, they have rhymes. It is commonly known as "Shuo Chun", and people who speak of spring are called "Chun Guan".

Sticky sparrow mouth

On the spring equinox, farmers eat dumplings at home. They also cook more than ten or twenty or thirty dumplings that are not wrapped in the heart. They cut them with bamboo sticks and put them on the side of the field outside. It's called sticky sparrow mouth, so as not to damage the crops.

Outing and kite flying

After the vernal equinox, people begin to go out for a hike. In outdoor activities, kite flying is an important project. In ancient times, there was the custom of drinking with hairpin flowers at the equinox. On this day, men, women, young and old would hairpin flowers.

Kites, known as "kites" in ancient times and "kites" in the north, have a history of more than 2000 years. "Kite" and "Kite" are hawk birds of prey, most of the kites used in ancient times

Chinese PinYin : Chun Fen