The sun will most likely illuminate Earth equally on both poles during September and March. On these months, Earth will not be tilted toward or away from the sun. This results to both poles receiving nearly the same amount of light, which means that the length of days and nights are equal all over Earth. This event is referred to as Equinoxes. During March, it is called the Vernal Equinox, while during September, it is called the Autumnal Equinox.