When Is The Vernal Equinox 2024 Usa. The vernal equinox — is an astronomical phenomenon when the sun, in its visible motion along the ecliptic, crosses the celestial equator. When is the first day of spring 2024?
When is the vernal equinox? The vernal equinox — is an astronomical phenomenon when the sun, in its visible motion along the ecliptic, crosses the celestial equator.