The official start to the fall season, the autumnal equinox, occurs on Sunday, Sept. 22.
What exactly happens during the equinox? Here’s a breakdown:
THE AUTUMNAL EQUINOX:
According to NOAA, an equinox occurs when the Earth’s axis is tilted neither away nor toward the sun.
This allows the sun’s position to reside directly over the equator, resulting in nearly an equal amount of day and night at all latitudes.
DIFFERENCE BETWEEN AN EQUINOX AND A SOLSTICE:
There are only two times of year when an equinox occurs: the start of fall (autumnal), and the start of spring (vernal).
The start of the summer and winter seasons are noted by solstices. A solstice occurs when the Earth’s tilt (either towards or away from the sun) is at a maximum.
>>>READ: A tale of 2 seasons: The difference between meteorological and astronomical seasons
After the autumnal equinox, the Northern Hemisphere will start to tilt away from the sun as the Earth continues its revolution, leading all the way up to the winter solstice which occurs on Saturday, Dec. 21.
Regarding daylight hours, the winter solstice marks the shortest day of the year and the longest night. Conversely, the summer solstice marks the longest day of the year and the shortest night.
As the amount of daylight decreases into the fall season, clocks will “fall back” one hour on Sunday, Nov. 3.
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