SPRING EQUINOX: The first day of the Season of Spring - and the beginning of a long period of sunlight at the Pole. In the northern hemisphere: MARCH 20 (the Sun crosses the Equator moving northward). In the southern hemisphere: SEPTEMBER 22 (the Sun crosses the Equator moving southward).
AUTUMN EQUINOX: The first day of the Season of Autumn - and the beginning of a long period of darkness at the Pole. In the northern hemisphere: SEPTEMBER 22 (the Sun crosses the Equator moving southward). In the southern hemisphere: MARCH 20 (the Sun crosses the Equator moving northward).