vernal equinox point; vernal equinox
Astronomical term for the point on the celestial sphere where the sun crosses the celestial equator from south to north, marking the beginning of spring in the Northern Hemisphere.
The vernal equinox point is one of the two points where the celestial equator and the ecliptic intersect.
When the sun passes the vernal equinox point, day and night become nearly equal in length.