PHOENIX - It's official! Tuesday at 2:18 p.m. marked the beginning of fall.
The start of the season, called the autumnal equinox, happens when the sun is directly over the equator.
The result - for just a short while at this time of year - is that days and nights are approximately equally long.
From here, the sun starts to move south for the winter, creating longer nights and shorter days in the Northern Hemisphere (and the reverse in the Southern Hemisphere).
The term "equinox" is actually derived from the Latin
aequus (equal) and nox (night).For those of you who do not know what this event really is, you should know that an equinox happens twice a year. We have the Vernal (Spring) equinox and an Autumnal (Fall) equinox.
The equinox doesn’t last one whole day; the event only represents a single moment in the day when - at the equator - the Sun’s center can be observed to be exactly vertically overhead.
The equinox occurs when the tilt of Earth’s own axis is inclined neither away from nor towards the Sun.
There is no "winter" or "summer" at this moment - there is simply the changing of seasons.
The equinox can happen on March 20 or 21 (for spring), and on September 22 or 23 (for fall) each year.
The good news is that a taste of autumn will actually arrive in the Valley by Wednesday with lower temperatures. Can you say below 100!?
Happy equinox day!
