What does the vernal equinox mean?

The vernal equinox is one of the 24 solar terms and the fourth solar term in spring.

At the vernal equinox, the solar meridian reaches 0, and it meets on March 19-22 of the Gregorian calendar every year. The vernal equinox is of great significance in astronomy. On this day, the northern and southern hemispheres are divided equally day and night. Since then, the direct position of the sun has continued to shift from the equator to the northern hemisphere. The days in the northern hemisphere are longer than the nights, while the southern hemisphere is the opposite.

Climatically, there are also obvious characteristics. In addition to the Qinghai-Tibet Plateau, Northeast China, Northwest China and North China, China has entered a beautiful spring. 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.

After the vernal equinox, the climate is mild, rainy and sunny. During the vernal equinox, there are some folk customs in China, such as flying kites, eating spring vegetables and laying eggs.

Historical origin:

The "vernal equinox" means half, that is, it is divided into two parts, day and night are equally divided, and the cold and summer are balanced. In addition, the vernal equinox also means sharing spring equally. Traditionally, it is spring from beginning of spring to long summer, and the vernal equinox is in the middle of three months in spring. Therefore, the vernal equinox was also called "Japan-China", "Day and Night Equinox" and "Midspring Moon" in ancient times.

At the vernal equinox, the sun shines directly at the equator of the earth, and the length of day and night is equal. According to Yuan Wucheng's book "Twenty-four Solar Terms", "In mid-February, it is divided into 90 days and a half, so it is called division."

Another "Spring and Autumn Story" said: "The vernal equinox, Yin and Yang are also half-phase, so day and night are cold and summer." Lunar Book: "The bucket refers to the vernal equinox, which is about Sunday, and the northern and southern hemispheres are equally divided day and night (except the poles), which is also half of spring, so it is called the vernal equinox."