The March equinox, occurring on March 20, marks the beginning of spring in the Northern Hemisphere and autumn in the Southern Hemisphere. While it is often believed that day and night are equal on this day, in reality, daylight slightly exceeds nighttime due to the sun's size and atmospheric refraction. This event signifies Earth's axial tilt aligning with the sun, resulting in nearly equal daylight hours across the globe. Celebrations and cultural festivities accompany this astronomical phenomenon, symbolizing renewal and change.
Source: EarthSky