March Equinox 2024 Uk. The equinox in the northern hemisphere occurs twice a year around 20 march (the spring equinox) and around 22 september (the autumn equinox). The spring equinox (march 19, 2024) signals the start of spring in the northern hemisphere, the beginning of autumn in the southern hemisphere, and a rare moment.
On the day of the spring (march) equinox, the sun crosses the celestial equator, moving along the ecliptic. On this date, the day is equal in length to the night.