The equinox is the point where one season turns to the other. The word is Latin for 'equal night' and refers to the fact that, on the equinox, day and night are of equal length. There are two equinoxes each year, with the vernal equinox usually occurring on 21 March. Vernal comes originally from the Latin word for 'bloom' - it refers to the fact that, in the northern hemisphere, this equinox marks the end of winter and the beginning of spring. The name is less meaningful in the southern hemisphere, where this equinox actually marks the beginning of autumn, but nonetheless the traditional name vernal is commonly retained...
