The vernal equinox.

The composition is filled with auxiliary elements and symbols, as well as conventionally divided into two parts, a clear spring day and a deep cosmic night. Light and darkness are divided equally. In ancient times, when there were no calendars, spring was determined by the sun. It was believed that it is from this day begin to renew in nature: the first spring thunder, the swelling of the buds on the trees, the violent germination of greenery.