Navigating at Night without a compass

The Stars

The sun, moon, stars and planets all play a role in celestial navigation and before the advent of technology; sailors learned how to navigate their ships even at night time by relying on this method. Although it can’t be 100% accurate, it can give you a good indication of the general direction in which you’re heading.

Remember that the sun always rises in the east and sets in the west but not exactly due East or Due West. That depends on the season and where you are located in the northern hemisphere. When it reaches its highest point at 12:pm (noon), its direction will be true south in the northern hemisphere. The North Star or Polaris determines a northerly direction in the northern hemisphere and although it’s not the brightest star as you may have heard, it’s important because unlike the rest of the stars in the night sky, its position remains fixed in the same place all the time, so if you follow it, you know that you are heading north.

By being able to locate much more recognizable constellations on a clear night such as the Big Dipper (shaped like a one handled wheelbarrow) and Cassiopeia (shaped like the letter ‘W’), you’ll find it much easier to locate the North Star and it’s useful to do some research on maps of the night sky to aid you with navigation by the stars.

If you locate Ursa Major or "The Big Dipper: as shown in the photo below, draw direct line off the ladle towards Cassiopeia you'll cross the handle of Ursa Minor or "The Little Dipper". The last star on Ursa Minor's "handle" is Polaris or "The North Star" .

Finding Polaris or True North
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Polaris Photo: This file is in the public domain because it was created by NASA and the European Space Agency. Hubble material is copyright-free. Material published by NASA may be freely used as in the public domain without restriction, although NASA requests credit and notification of further use. ESA requires that they be credited as the source of any of their material that is used. The material was created for NASA by STScI under Contract NAS5-26555 and for ESA by the Hubble European Space Agency Information Centre.

The Moon

The moon is a compass or more accurately a pointer to the north star. So if you can see the moon you should be able to find north. There are two ways to do this.

The first way involves knowing something about the "look" of the moon or more specifically it's patterns. On a fairly full moon you can see a crescent of shadows. On the picture below the finger in the full moon points to the north.

Showing North on a full Moon
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When the moon is at a phase where you can see where the "crescent" starts you can find north by making an imaginary line from the tips of the crescent to the north star. Or where the north star is. If you look real close in this picture below, you can see that the line drawn from the tips of the crescent also cross the finger in the shadows as well. It's not perfect, but I did my best "artist" impression. Many times when the moon is at different stages you can't really see the detail as pictured below, therefore drawing the imaginary line may be more accurate.

If you notice how far this is at night, you can measure this same distance in the day to find north.

Showing North on a full Moon
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Because the moon simply reflects the sun’s light and produces no light of its own and because of what we know about the sun’s daily pattern, we can also use the moon for direction at certain phases of its monthly progress. If it’s in a crescent phase, simply draw an imaginary line between both tips of the crescent and on downwards until you reach the horizon. The point where it touches the horizon is approximately South in the northern hemisphere. And, if the moon rises before the sun sets, the illuminated side will be west but if it rises after dark, the illuminated side will be east.

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