Just about everyone knows how to find the compass directions during the day. In the morning the sun rises in the east, in the evening it sets in the west. But, how can one determine the compass directions after the sun has set?

On any night with a waning, waxing or crescent moon, its simple. Since we know that the moon is illuminated by the sun, the same technique applies as it does during the day.

First, all we have to do is draw an imaginary line between the boundary between the moon’s illuminated side and that which is in shadow. Then simply draw an imaginary line perpendicularly to the horizon. In the early hours of the night, this line points west towards where the sun recently set. In the the late hours of the night, this line points towards the east where the sun is to rise. Simple, right?