TERMS FOR DESCRIBING LUNAR PHASES:
New ==> Waxing Crescent ==> First Quarter ==>
Waxing Gibbous ==> Full ==> Waning Gibbous ==>
Third Quarter ==> Waning Crescent ==> New
The Lunar Phase tells you the angle between the Sun and the Moon.
Check this movie!
Set "Point of View" to "Both".
Since we can see half the sky, that means the Moon is above the horizon for approximately 12 hours. But the particular 12 hours depends on the PHASE of the Moon. Looking at the diagram below, the time below the phase of interest is the MIDDLE of the 12 hours, when that phase Moon is crossing the meridian. That means that phase Moon had to rise 6 hours earlier and set 6 hours later.
For example, from the diagram below, the time under the FIRST QUARTER is 6:00 pm. That means the FIRST QUARTER Moon crosses the meridian at 6:00 pm. In order to do that, the FIRST QUARTER Moon must rise 6 hours earlier, which is Noon. Then the FISRT QUARTER Moon sets 6 hours after crossing the meridian, which means that phase Moon sets at Midnight
So, the FIRST QUARTER Moon rises at NOON (12:00 pm), crosses the meridain at 6:00 pm and then sets at MIDNIGHT (12:00 am).
Easiest Lunar Phase Diagram to use for homework.
The LUNAR MONTH is the time period for the Moon to complete ONE REVOLUTION around the Earth.
The Synodic Month is the length of the Lunar Phase cycle.
Revolution Period = 27.3 days.
When the Rotation Period equals Revolution Period, this is called
