http://www.usno.navy.mil/USNO/astronomical-applications
If you determine the time of the transit of the sun at your location then the shadow cast by a vertical pole will point towards true north at your local apparent noon. You can then observe the difference between local apparent noon and civil noon. That is the basis of the noon site for celestial navigation just in case your gps fails and you don't know which side of the lake you are on.
If you determine the time of the transit of the sun at your location then the shadow cast by a vertical pole will point towards true north at your local apparent noon. You can then observe the difference between local apparent noon and civil noon. That is the basis of the noon site for celestial navigation just in case your gps fails and you don't know which side of the lake you are on.