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Is it possible to find directions just by looking at moon(not full bright)? I was curious to use the clue that if moon is half lit then the direction in which it is lit will it be east?

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2 Answers 2

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If you know what time of day it is, then this works fine. A half-full moon is either waxing (becoming more full), in which case it's known as first quarter, or waning (becoming less full), in which case it's known as last quarter.

A first quarter moon rises in the East at approximately noon and sets in the West at approximately midnight, and its bright side will be towards the Sun, which will be towards the West, because it is trailing the Sun.

A last quarter moon rises in the East at approximately midnight and sets in the West at approximately noon, and its bright side will be towards the Sun, which will be towards the East, because it is leading the Sun.

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wow, i was about to arrive at conclusion that it will always give the east. –  bubble Jun 22 '11 at 16:21
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Excellent answer, Ben. I would add that with the right gear you should be able to get your lat and long. This is called celestial navigation. GPS is making this a lost art. –  Vintage Jun 22 '11 at 21:46

In addition to having the moon "point" to the east or west, you can also roughly determine the location of the ecliptic by the location of the moon and the direction that it "points" to. Once you know the ecliptic, you can roughly determine where the North Star should be. This does require much more practice, though. Start practising at night.

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