An equinox occurs twice a year when the sun is directly above the equator, resulting in nearly equal day and night lengths across the globe. The two equinoxes are the vernal equinox, which happens around March 20 or 21, marking the start of spring in the Northern Hemisphere, and the autumnal equinox, occurring around September 22 or 23, signaling the beginning of fall. During an equinox, the tilt of the Earth's axis is such that it is neither tilted toward nor away from the sun. This unique position allows for a balance in sunlight, affecting seasonal changes and influencing various cultures and traditions related to the changing seasons.