Spring Equinox 2024. The vernal equinox marks the beginning of astronomical spring, while the autumnal equinox marks the beginning of autumn. It is also the point in the calendar where the day length is more or less equal.
The spring equinox is tuesday, march 19 and brings the first day of astronomical spring to the northern hemisphere. On march 19, the vernal equinox will see spring come to the northern hemisphere as the sun reaches the spot where the ecliptic and celestial equator cross each other.