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A diagram showing how the Sun moves through the sky on an equinox.
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The Spring and Autumn Equinoxes

The spring and autumn equinoxes occur around March and September 21. These are special points in the Earth's orbit when the Sun appears directly above the Earth's equator. Day and night are nearly the same length, about 12 hours.

The diagram to the left shows how the Sun may appear to move through your sky on an equinox, if you live at a latitude of 40° N, around Topeka, Kansas for instance.

The Sun is in between its altitude on the summer solstice (the highest point) and its altitude on the winter solstice (the lowest point). In a similar way, spring and autumn are in between summer and winter; the temperatures are neither very hot nor very cold, and the weather is not as extreme as in summer and winter.

Compare the Sun's height to what you would see in the winter or in the summer.

Last modified September 3, 2010 by Randy Russell.

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