What is the vernal equinox?

At the spring equinox, the rain falls lightly, and the slanting wind on the Liu 'an sends guests home.

The northern season is late, and I knew there was green waist fat.

-"Four Unique Awakening"

In the mid-spring when the spring is infinitely good, a most special solar term-vernal equinox is ushered in.

The vernal equinox is the fourth solar term among the 24 solar terms, and it is also the fourth solar term in spring, after the fright and before Tomb-Sweeping Day.

This year's vernal equinox is on March 20th 17:37: 19.

Why is it called vernal equinox?

According to the 24 solar terms, "the vernal equinox, in mid-February, divided by half, is 90 and a half days, so it is called division. Autumn is synonymous. "

It means that the vernal equinox is in the middle of February of the lunar calendar, when the 90 days of spring are just over half, so it is called "vernal equinox". The autumnal equinox means the same thing

The Spring and Autumn Story explains it this way: "The vernal equinox is half cloudy and half sunny, so it is cold and hot day and night."

This means that on the vernal equinox, Yin and Yang are equally divided, so day and night are equally divided, and the climate is equally hot and cold.

It can be seen that the vernal equinox has two meanings, one is to divide spring into two halves, and the other is to divide day and night, cold and heat equally at this time. It is almost synonymous with "balance" and "symmetry". So why is spring, day, night, cold and summer equally divided on the vernal equinox? This is related to the earth's rotation and revolution.

As we know, the earth revolves around the sun constantly. The plane on which the earth rotates is called the equator, and the plane on which the earth revolves around the sun is called the ecliptic. The angle between the equator and the ecliptic changes with time. Every year around the vernal equinox, this angle reaches a perfect 0, and the ecliptic is perpendicular to the earth axis. At this time, the sun is directly near the equator.

As a result, the sun shines on all parts of the earth impartially, and everything reaches an almost accurate balance. So there will be a phenomenon of equal day and night. On the vernal equinox, the whole world is divided equally between day and night, which is equal to 12 hour. Of course, China's northern hemisphere is no exception.

This phenomenon only happens twice a year, namely the vernal equinox and the autumnal equinox.

The whole spring is just over half at this time, and the whole country is full of warmth, brightness and vitality.

"Hua Xinfeng" has thrived.

In order to better reflect the climate change during the vernal equinox, the ancients divided the fifteen days in the vernal equinox solar terms into the following "three periods":

Waiting for the arrival of the mysterious bird.

A blackbird refers to a swallow. When the vernal equinox comes, swallows will fly back to the north from the south.

Second, wait for Renai to make a sound.

Although the spring thunder has gradually sounded, the thunder is still weak and will rumble after the vernal equinox.

Third, wait for the power to start.

In the last five days of the spring equinox solar terms, lightning began to appear in the sky, often with lightning and thunder.

Three "Hua Xinfeng"

During the spring equinox and solar terms, there will be many flowers blooming, and the three "Hua Xinfeng" are begonia, pear and magnolia.

Begonia flowers bloom in mid-spring, and the flowers are bright and charming. They have the reputation of "fairies in flowers" and "nobles in flowers", and have always been deeply loved by Chinese people, especially literati. They have a soft spot for begonia flowers and there are countless poems praising begonia.

Li Qingzhao, a talented woman in the Song Dynasty, was still worried about the begonia in the hospital when she was drunk, and wrote: "If you want to ask about the shutter, the begonia is still there"; Su Shi is also very kind to Haitang, and there is a quip, "I am afraid that flowers will fall asleep at night, so I light a candle and shine red makeup"; Lu You once praised that "comfortable makeup makes people feel colorless before flowers". In Shu's view, the most beautiful thing is not the girl, but the begonia flower.

In A Dream of Red Mansions, the sisters of Grand View Garden set up a Haitang Poetry Society in the season when Haitang was in full bloom, and recited many beautiful Haitang poems with the theme of Haitang, among which Lin Daiyu, the concubine of Xiaoxiang, wrote the most touching poem "Ode to White Sea Tang":

Half-rolled curtains cover the door, and the ice is ground into earth jade as a basin.

Steal a pear for three cents and borrow a plum blossom for a soul.

Half a roll of ChristianRandPhillips bamboo curtain, half a door, broken ice as soil, plum rain as a flowerpot. Its three-point snow seems to have been stolen from the pear core, and the fragrant soul seems to have been borrowed from the plum blossom.

In five days, the pear blossoms will be in full bloom. Pear flower is fresh and elegant, famous for its white color, and it is the most beautiful scenery in mid-spring. Especially in the continuous spring rain, the "pear flower with rain" of a tree is really fresh and moving. Compared with the s-curve peach blossom, pear blossom is endowed with higher quality, so Huang Tingjian praised:

"Peach blossoms are all red, not as good as natural jade."

After the pear blossoms, magnolia blooms one after another. Magnolia in this solar term mainly refers to magnolia purpurea. As early as the solar term in beginning of spring, magnolia had already bloomed in the whole forest area. In ancient times, Mulan was often used to refer to women, because there are allusions that Mulan joined the army as her father.

These spring phenology are announcing to the earth that sunny spring has come in an all-round way.

"Spring Equinox Sacrifice to the Sun" and its Customs

The ancient people's respect for the sun is self-evident. Since the Zhou Dynasty more than 2,000 years ago, a grand ceremony of offering sacrifices to the sun has been held every spring equinox. This ceremony lasted until the Ming and Qing Dynasties.

Books in the Qing Dynasty contain the following words: "The spring equinox sacrifices the sun and the autumn equinox sacrifices the moon, which are the grand ceremonies of the country, and scholars are not allowed to worship at will."

This shows its importance.

In addition to the official, ordinary people also have their own unique festivals. Before the vernal equinox, people will steam a kind of cake called "sun cake" in advance. In the early morning of the vernal equinox, people will place sun cakes, incense burners and other items in the center of the altar. At the moment when the sun rises, the whole family worships the East.

Nowadays, these festivals have been cancelled for a long time, but the sun cake still stays on the table because of its sweetness. The world's awe of the sun has not diminished at all, and it has been replaced by a more scientific and effective way to explore and understand the sun.

Vernal equinox and eggs

There is also an ancient and interesting game in the spring equinox solar terms, which even spread abroad, and that is "vertical eggs". Here's how to do it: Choose a fresh egg with a smooth surface that has just been laid for four or five days, gently put it on the table and try to stand up.

"When the vernal equinox comes, eggs are beautiful." At the vernal equinox every year, many children get together to play this game. It is said that those who succeed in "laying eggs vertically" will have good luck this year.

Why do people think that eggs on the vernal equinox can stand upright? In fact, this is scientifically justified.

As mentioned earlier, at the vernal equinox, the earth is in a perfect balance, and day and night, cold and summer are equally divided. At this time, gravity is relatively stable, and it is easier to erect the eggs. Moreover, there are some small protrusions on the surface of the egg, which can help the egg to be stable.

Flower Festival

Flower Festival, also known as "Flower God Festival", is a festival to commemorate the birth of flowers. The dates vary from place to place, but they are all in February of the lunar calendar, that is, the spring equinox solar terms. Flower Festival is a very important festival in ancient China. It is said that Kao is in charge of human fertility, so ancient women paid special attention to it.

By the Tang Dynasty, the Flower Festival had been formed. As a woman, Wu Zetian is naturally infatuated with flowers. Every spring, when all the flowers are in full bloom, she lets the ladies-in-waiting go to the world to pick flowers, make them into flower cakes and give them to ministers. Folks have followed suit and picked flowers to make cakes.

In the Song Dynasty, the Flower Festival was very popular, and various festivals were also very rich, not only offering sacrifices to the flower gods and giving flowers birthdays, but also going out to enjoy flowers. Women all like to meet and participate in the "butterfly fluttering party", while men like to drink and write poems under the moon.

Su Shi's masterpiece Spring Night describes the beauty of the Flower Festival;

Spring night is worth a thousand dollars, and the flowers are fragrant and the moon is cloudy.

Song Guan balcony sound fine, swinging yard night heavy.

A bright night in spring is infinitely beautiful, and the moment of time can be worth a thousand dollars. Flowers are blooming and the moonlight is hazy. The balcony in the distance kept singing and dancing, and the songs came carefully and floated into the swing courtyard with heavy night.

Dietary customs

The food that must be eaten at the vernal equinox and solar terms is "spring vegetables". Spring vegetables in Lingnan area refer to wild amaranth, and locals call it "Chrysanthemum morifolium", which grows most luxuriantly around the vernal equinox. So every vernal equinox, people dig wild vegetables in the spring and make wild amaranth and fish fillets into "spring soup". In the north, spring vegetables refer to vegetables such as lettuce.

In some areas, jiaozi is also eaten at the vernal equinox. When farmers are full, they will put the remaining jiaozi on bamboo poles and stand in the fields. This strange practice is called "sticking sparrows' mouths", because farmers hope that these jiaozi can stick sparrows' mouths so that they can't steal crops from the fields.

In addition, there are customs such as brewing wine, eating noodles in soup and eating noodles in noodles.

The precise balance and symmetry of the solar terms in the vernal equinox perfectly satisfy China people's pursuit of the aesthetic feeling of the golden mean. Time flows so accurately that there has never been any mistake for thousands of years, so the earth has created a miracle of life and mankind has created a brilliant civilization.

Nature also reached its best balance at the vernal equinox. In this mid-spring season, birds are singing and flowers are fragrant, and everything becomes beautiful and colorful at the right time.