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Autumnal Equinox – Fall Equinox

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When is the Autumnal Equinox in my city?

Equinoxes are opposite on either side of the equator, so the autumnal (fall) equinox in the northern hemisphere is the spring (vernal) equinox in the southern hemisphere and vice versa.

Why is it called "Equinox"?

On the two equinoxes every year the sun shines directly on the equator and the length of day and night is nearly equal – but not exactly.

First day of fall?

In the USA and some other areas in the northern hemisphere, the autumnal equinox marks the first day of fall (autumn). However, the official date for the first day of fall varies depending on the country's climate.


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