Vernal Equinox 2024 Date. An equinox is one of two days in the year when the sun crosses the equator and day and night become equal in length. The vernal equinox — is an astronomical phenomenon when the sun, in its visible motion along the ecliptic, crosses the celestial equator.

 — equinoxes and solstices are two of the most important celestial events on earth. Know the significance of the special.