Autumnal Equinox

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There are lots of ways to track the passage of time. Watches and clocks and calendars abound. We carry them everywhere -- on our wrists, in our pockets and purses, on the dashes of our cars. And yet in many ways, we're less in tune with the rhythms of time than were our ancestors of centuries past. They relied not on the mechanical parsing of time into its tiniest divisions, but on the long and gentle cycles of the Moon and, especially, the Sun.

Today is an important day in one of those cycles -- the passing of the seasons. It's the September equinox -- the start of autumn in the northern hemisphere, and spring in the southern hemisphere. It arrives at 10:44 a.m. Central Daylight Time as the Sun crosses the celestial equator from north to south. More practically, the Sun rises due east and sets due west today, and the day and night are almost exactly equal lengths.

In many societies, priests or shamans watched for the equinoxes and other important dates by tracking the Sun's motion across the horizon.

The arrival of the fall equinox indicated that it was time to harvest the crops or to begin other preparations for the cold winter months ahead. Many tribes moved to better hunting grounds, or simply built up their stocks of food and fuel -- practical responses to the rhythm of the Sun. So tracking the passage of time was a matter of survival, making sunwatching one of the most important jobs in the ancient world.

Script by Damond Benningfield, Copyright 2008

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