It is the vernal equinox and solar terms that make up a number.

The vernal equinox and solar terms make up the number 24.

The vernal equinox is one of the 24 solar terms and the fourth solar term in spring. The meridian of the sun reaches 0, and [2 1] intersects 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.