002.1 Phases of the Moon
The waxing Gibbous Moon is visible from sunset (sometimes before sunset) until well after midnight.
The Gibbous Moon will be visible for several hours. If you observe the stars that are near the Moon and then look again in an hour, you will see that the Moon has moved relative to those stars. How many times the apparent diameter of the Moon will the Moon have moved?
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The Moon moves once (Eastward) around the Celestial Sphere every Sidereal Month. There is a slight difference between a regular month and a Sidereal month, but, for this rough calculation, we can ignore it. Thus, it moves through 360° roughly every 30 days or 12 degrees per day. Since there are 24 hours in a day, it moves 1/2 degree per hour. The angular diameter of the Moon is about one degree, so it moves through half of its apparent diameter each hour.