How to find south using the moon shadow

Did you know that you can find south by drawing a line across the shadow on the moon and then locate the point where the line intersects the ground. My beautiful illustration below hopefully makes it clear how this works.


I read this in a Swedish historical magazine (Världens Historia) a few days ago but was not convinced, so I have tested the theory for a few days by observing the moon and following the line to the ground. And to my amazement it seems to work!

Looking for confirmation I also found this text at Scouting Ireland: "Because it reflects the sun’s light, the moon always points towards the sun, and thus even at night indicates the direction of the sun. Whether the moon is waxing or waning, an imaginary line through the horns of a crescent moon will always give you, approximately, a north-south line." I’m not 100% sure this is identical with what I say above, but it’s close enough!

Feel free to impress friends and family during the holiday season with your deep knowledge of how to navigate at night without a compass.