As the Northern Hemisphere welcomes spring today, the Southern Hemisphere greets the first day of autumn. The word equinox is derived from the Latin words "aequus" (equal) and "nox" (night).
In the northern hemisphere, there are two vernal equinoxes each year: the spring equinox, which takes place between 19 and 21 March, and the autumn equinox, which takes place between 21 and 24 ...