First Day Of Spring 2013: What is the March Equinox?

The March Equinox has arrived!

Since the last time you heard that phrase was probably the fourth grade, a quick science lesson is in order.

Equinox comes from the Latin words for "equal" and "night," because the equinox is the one day of the year when the lengths of day and night are equal.

This happens because, twice a year, the sun's rays hit the Earth straight-on at the Equator.

Usually, since the Earth is tilted at an angle, the sun's rays hit either the northern or southern hemisphere more intensely, creating opposing winters and summers.

Below shows what is winter for the northern hemisphere and summer for the southern. 

However, at the March and September Equinoxes, the Earth is directly facing the sun, creating an equal day and night and marking the change of seasons.

What does that actually mean for us today? It's the first official day of spring for those of us in the Northern hemisphere! (for those like me who have just been barraged with snow, take heart).

But while the March Equinox may not be much more than a phrase on a calendar in this day and age, in the past, it was used to (somewhat inaccurately) calculate the length of the year – and many countries' calendars — like India and Iran — still base their New Years on the Equinox.

If you follow those calendars, have a happy new year!

If not, feel free to celebrate World Storytelling Day, the Burning of the Socks, International Astrology Day, or just bask in the knowledge that a change in the weather is soon to come.