When is the vernal equinox?

The vernal equinox solar terms meet on March 19~22 of the Gregorian calendar every year.

The sun shines directly on the equator of the earth, and day and night are almost equal. In ancient times, it was spring from beginning of spring to long summer, and the vernal equinox was in the middle of three months in spring. The sun reaches the longitude of the yellow meridian at 0 degrees, and the solar calendar is in March 19~22 every year. "The vernal equinox, Yin and Yang. Therefore, it is hot and cold all day long. "

The book of the lunar calendar records: "It refers to the vernal equinox, which is about Sunday. The northern and southern hemispheres are equally divided day and night, which is also half of spring, so it is called the vernal equinox." From this day on, the direct position of the sun gradually moved northward, and the length of day and night in the northern and southern hemispheres also changed. The northern hemisphere has long days and short nights, but the southern hemisphere is just the opposite.