How to Determine Direction

Page 5

The previous methods of determining direction by field expedient means are useful during the day, but what about at night?

Determining direction at night can be just as easy as it is during the day, and perhaps even easier. But, you must be able to see the stars, in particular the North Star and the Big Dipper.

The North Star (also known as Polaris) is a star that almost remains stationary as the earth turns on its axis. The North Star is positioned very nearly over True North, that is, the earth's north pole. If you looked at a time lapse photograph of the North Star, it is pretty much a dot surrounded by circular streaks of light. These circular streaks of light are the rest of the stars moving across the sky while the earth turns. The trick is to find this North Star among the thousands of other stars visible at night. 

The constellation of the Big Dipper provides a means of doing just that. 

The Big Dipper is a constellation in the northern part of the sky. It is so named because its shape looks like that of a long handled sauce pan or dipper. It is also called the Great Bear or Ursa Major in some publications.

To find the North Star, stand out in an open area, and look for a group of stars that looks like the Big Dipper in the picture below. The exact orientation of the Big Dipper depends on the season and time of the night. Take an imaginary line from the two pan stars (farthest from the handle) and continue this line to a medium bright star. This is the North Star. This can be further confirmed by continuing this imaginary line until you just miss a constellation that looks like a large "W" or "M." This is the constellation Casseopea. The North Star is almost half way between these two constellations.

Points to remember:

1. The North Star is a Medium Bright star, not a very bright star.

2. The Big Dipper and Cassepea move in a circular motion around the North Star, so the exact position of these two constellations will be different as the seasons, and time of night, change.

3. The Big Dipper and Casseopea are not directly across from each other, but almost.

4. The North Star is not directly between the two constellations, but almost.

5. If you face the North Star, south will be directly behind you. If you raise your left arm, it will point west. Raising your right arm will point east.

Use the North Star at night to kept your sense of direction. As an example, walking with the North Star off your left shoulder will keep you moving EAST. If you walk with the North Star off your right shoulder, you will be walking WEST. If your walking with the North Star behind you, your obviously walking SOUTH, and so on.

The time to learn how to determine direction using these field expedient means is BEFORE they are needed. Practice them in a controlled environment, and you can rely on that knowledge when it is needed.

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