The longitude of the sun reaches 0, and the festival is held on March 19-22 of the Gregorian calendar every year. "Equinox" has two meanings. One is "season sharing". Traditionally, spring is between beginning of spring and Changchun, and the vernal equinox is in the middle of the two solar terms, which just divides spring equally. Another meaning is "equal day and night". At the vernal equinox, the sun shines directly on the equator, and the length of day and night is equal, each being 12 hour.
The climate of the vernal equinox is characterized by warm and sunny weather. The vernal equinox is of great significance in astronomy. On the day of the vernal equinox, the sun shines directly on the equator, and the northern and southern hemispheres are divided equally day and night. Since then, the direct sunlight position of the solar nucleus has continued to move from the equator to the northern hemisphere, and the days in the northern hemisphere began to be longer than the nights, while the collapse in the southern hemisphere was the opposite.
Climatically, there are also obvious characteristics. After the vernal equinox, China has entered a beautiful spring except the Qinghai-Tibet Plateau, Northeast China, Northwest China and North China. At this time, China folks have the custom of flying kites, eating spring vegetables and laying eggs.
Equinox health:
The vernal equinox diet pays attention to "regulating its yin and yang, supplementing if it is insufficient, and diarrhea if it is surplus". At this time, eating more fruits and vegetables can supplement the consumption of vitamins and minerals in winter, which is of great benefit to health.
Compendium of Materia Medica records that Folium Artemisiae Argyi is warm, bitter and non-toxic, and has the functions of restoring yang, regulating qi and blood, eliminating dampness and dispelling cold, stopping bleeding and preventing miscarriage. It is also often used in acupuncture. At this time, it is also the most fertile season for yellow sand clams. In Guangzhou, clams are generally fried with leeks, which are crisp and tender.