How to Navigate by the Sun: A Simple Trick

When the sun reaches its highest point in the sky, it can always be found due south. This is often referred to as "high noon," although the correct astronomical term is "solar noon." The precise time it occurs varies depending on the time of year and your location within the time zone.

For example, on August 26 in Boston solar noon occurs at 12:43 P.M.; in New York City at 12:57 P.M.; and in Pittsburgh, Pa. at 1:22 P.M. Three months later on November 26, the times are 11:32 A.M., 11:43 A.M., and 12:07 P.M. respectively. The changes are caused by two things: 1) time has shifted back to Eastern Standard Time from daylight savings and 2) the sun's path across the sky has subtly shifted with the seasons. (One of the best sites I've found for looking this up is www.timeanddate.com. Here's the direct link to Boston sun data, including solar noon.)

So if it's close to solar noon, then the sun is in the south. Consequently, shadows all point to the north. (Interestingly, the situation is reversed in the southern hemisphere, where the sun is in the north at solar noon.)

As a rough approximation, the sun also moves about 15 degrees across the sky from east to west as the day progresses. So based on the time of day and approximate solar noon, you can also roughly determine where the sun is at any given moment. For example, in Boston at 4 P.M. on August 26, the sun will be ~45 degrees past due south and in the southwest, with shadows pointing to the northeast.

Equipped” is an AMC Outdoors blog, written by Matt Heid.

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