What exactly is the spring equinox? Divided the spring equally, divided the day and night equally, and divided the cold and heat equally.
The vernal equinox, the fourth solar term of the year. "Divide", explained by the Shuowen Jiezi as "don't also", is to use a knife to cut things in half. What is the spring equinox, this "knife" that cuts through time? The spring was divided equally, half before and after; day and night were equally divided, and the length of day and night was equal; the cold and heat were equally divided, and the balance between cold and heat was achieved. The "Explanation of the Seventy-two Waiting Episodes of the Moon Order" says: "Half of the dividers, this should be the half of the ninety days." "Spring and Autumn Dew" said: "The spring equinox, yin and yang are half, so the day and night are even and the cold and summer are flat." "At the spring equinox, the sun shines directly at the equator, but does it not just divide the spring equally, divide the day and night equally, and divide the cold and heat equally?" The scientific nature of solar terms is evident.
The vernal equinox is also one of the most important solar terms. The ancients "immediately see the effect", the easiest to find is the "winter solstice" when the shadow is the longest and the "summer solstice" when the shadow is the shortest. From the winter solstice to the summer solstice, the midpoint is the "vernal equinox"; from the summer solstice to the winter solstice, the midpoint is the "autumn equinox". "Two to two points" has become the first four solar terms discovered, which constitute the most basic framework of the solar term system.
Compared with other solar terms, the vernal equinox has an additional layer of meaning. There are three ways to measure solar terms, the first method is "bucket to star shift", observing the direction of the handle of the Big Dipper at night to determine the solar term. The second method is "immediate results", measuring solar terms by the length of the shadow. Both methods divide the time of year into 24 equal parts, which is called the "calm gas method". In fact, the Earth's orbit around the Sun is an elliptical orbit, and the Earth is slightly faster at perihelion and slightly slower at the aphelion, so the solar terms are not strictly divided in time. After the introduction of Western astronomical knowledge in the Ming Dynasty, the famous astronomer and mathematician Xu Guangqi presided over the third method, introducing the concept of solar ecliptic to measure solar terms. The ecliptic is essentially the earth's trajectory around the sun for a year, but from Earth, it is the trajectory of the sun moving in the sky throughout the year. Divide the 360-degree ecliptic into 24 equal parts, each 15 degrees, for a solar term, which is called the "definite gas method". Although it is all 15 degrees, the time to walk through each 15 degrees is slightly shorter, which is more in line with the real situation of the sun's movement. The method of fixing gas begins with the vernal equinox, which is the zero degree of the ecliptic at this time, and for every 15 degrees increased in turn, there are twenty-four solar terms. In 1645, the Qing government promulgated and implemented the Law of Fixing Gas. Xu Guangqi is a native of Shanghai County, and the "Xujiahui" in Shanghai is named after him.
Each solar term is divided into three seasons. The first day of the spring equinox is "Gentoro Solstice". The bird is the swallow, "helpless flowers fall, déjà vu swallow returned." "Swallows are the darlings of poetry. Open a swallow flying flower order, the master can fight until the sky is dark. The second time, "Thunder is sounding", the thunder that was sparse at the time of the sting is now dense. "The thunder of Jiangpu was noisy last night, and the rain in Spring City was slightly cold." The third "first electricity" began to have lightning. Thunder and lightning go to work collectively, and nature ends the silent film era and becomes sound and colorful.
There are many customs of the spring equinox. The most common is kite flying, "children return from school early, busy taking advantage of the east wind to fly paper kites." The most interesting thing is the "vertical egg", on the day of the spring equinox, people all over the world are busy putting the eggs up, and some people are studying the scientific truth behind it. How this "Chinese custom" has become a "world game" of popular countries is interesting. Digging wild vegetables is also one of the customs, my hometown in the southwestern Anhui mountains are rich in cabbage, water chrysanthemums and maoxiang, every time at this time is my nostalgia.
Qin Guan said, "The willows are peachy, and the spring colors are chaotically divided into people's homes." "Three flower trade winds at the spring equinox, first of all begonias," the east wind swept across the sogo, and the incense mist was empty of the moon corridor. I was afraid of going to sleep late at night, so I burned a high candle to illuminate the red makeup. "Waking up with candles, Su Shi's feelings really filled me with admiration for this predecessor thousands of years later." The second is the pear blossom full of trees, or Su Shi, "The pear blossom is pale white and the willow is deep blue, and the flowers are full of flowers when the willows fly." "There is nothing more beautiful in the verses of spring. Three waiting for Mulan, Wang Wei wrote Xinyi flower, "wood end hibiscus flower, red calyx in the mountains", Xinyi flower is a magnolia flower. "Magnolia blossoms on the hill, the spring of the northern country has arrived", where the magnolia is a symbol of spring.
The vernal equinox is not just these three flowers. The early blooming flowers have not yet been thanked, and the late blooming flowers have started, which is the season when a hundred flowers are in full bloom and the Buddha will be moved. Grasp the flowers, how many times can people see flowers bloom in their lifetime!
Author: Han Kesheng (Xinmin Evening News, Luminous Cup)
Editor: Gong Zijun