http://analyzer.depaul.edu/paperplate/Moon%20Finder.htm
The sun indicates the time, rotating clockwise once every 24 hours. When the sun is low along the eastern horizon, the time is sunrise (or simply AM). When the sun is high and due south, the time is noon. When the sun is low along the western horizon, the time is sunset (or simply PM). When the sun is opposite the noon position and below the horizon, the time is midnight.
When the sun is between those four positions, interpolate for time. This will compensate for some inaccuracies that become amplified near the solstices. Using the sun as a time indicator, set the sky to an approximate time. Though the sun indicates the time, refrain from referring to the sun as a "clock." Users tend to envision a 12-hour clock face rather than determining the time from the sun's position relative to the local horizon.
When using the Moon Finder, focus on only one moon phase and the sun at a time. Notice how the angle between the sun, the earth, and the moon remains the same whether the system is viewed from the earth or from the God's-eye perspective for the respective phases.
From a calendar or a newspaper or from observation, determine the current moon phase. Use the Moon Finder to determine when that moon rises, transits, or sets. Note how the full moon always rises as the sun sets and sets as the sun rises. Also note why most people are more familiar with the first quarter moon than the last quarter moon by virtue of the practical hours they are each visible in the sky.
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