Spring Vernal Equinox 2025. In the northern hemisphere, the march equinox (or spring equinox) determines the first day of spring—and this year, it falls on march 20. Vernal / spring equinox 2025 the spring or vernal equinox marks the astronomical first day of spring.
Spring equinox 2025 (beginning of astronomical spring) on the day of the spring (march) equinox, the sun crosses the celestial equator, moving along the ecliptic. It is also the point in the calendar where the day length is more or less equal to the.