The two solar terms as long as day and night are

The two solar terms as long as day and night are the vernal equinox and the autumnal equinox.

The vernal equinox refers to the fourth of the 24 solar terms, which means that in the middle of spring, day and night are equal in length. The vernal equinox is the midpoint of 90 days in spring. On this day, the sun shines directly on the equator of the earth, and the seasons in the northern hemisphere are opposite. In the southern hemisphere, this is the vernal equinox.

The autumnal equinox refers to the sixteenth day of the twenty-four solar terms, which means that in the middle of autumn, day and night are equal in length. At the autumnal equinox, the climate in the south begins to enter autumn from this solar term, and the 24-hour day and night is divided into 12 hours, so there is no extreme day and night phenomenon in the world.