John Wheeler, WDAY, Published September 21 2010
Weather Talk: Dispelling myths about the autumnal equinoxWednesday night at 11:09 p.m., the sun will cross the celestial equator. This moment, known as the autumnal equinox, varies year by year between Sept. 21 and 24, owing to our calendar being reckoned by 24-hour days.
The equinox moves forward about six hours each year and then gets thrown back a day every leap year.
There are a number of misconceptions surrounding the equinox. One is that day and night are of equal length on this day. This is only approximately true. Day and night are both around 12 hours, but they are not exactly the same length.
Gravity and balance are not affected by the equinox at all. An egg is not easier to balance on its end on this day.
The moment of equinox is also not related to any change in weather and should not be associated with any sort of “official” change of the season.
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