When night falls and the sky is clear, the moon can become a valuable tool for navigation. Unlike the sun, its light depends on its position relative to the Earth and the sun.
In this article, discover two simple techniques to determine an east-west line by observing the lunar phase and the time of its rise.
1. Read the direction from the illuminated edge
The moon does not produce its own light: it reflects that of the sun. Its visible shape changes according to its position in its 28-day cycle. If you see a crescent on the right side, it means the moon is waxing and the west is on the illuminated side.
If the crescent is on the left, the moon is waning, and thus east is on the illuminated side.
This simple observation allows you to mentally trace an approximate east-west line, very useful if you are lost at night.
2. Use the time of the moonrise
Observe the time at which the moon appears in the sky. If it rises before sunset, its illuminated edge is facing west. If it rises after midnight, the light is directed towards east.
This gives you a clear indication of direction, especially if you combine this observation with the position of shadows or fixed stars.
Conclusion
Even without daylight, it is possible to orient oneself by observing the moon.
By learning to recognize its phases and understand its trajectory, you can find a reliable direction, even in the heart of the night and without equipment.
