Description:Spring is here. And so is the Spring Equinox. Or is it the solstice? Equinoxes occur twice a year. The one in March is also referred to as the Vernal equinox, the one in September the autumnal equinox. Simply put, it's the day during which the sun rises and sets directly above the equator. To better understand why this phenomenon occurs and what it signals, it helps to understand how the Earth rotates around the Sun. Rather than circling the Sun at a right angle the Earth's rotational axis has (1:10)