The moon revolves counterclockwise around the Earth as the Earth revolves around the Sun. The moon’s period of revolution is 27 1/3 days. The moon also rotates on its axis. One full rotation of the moon is also 27 1/3 days. The same side (or face) of the moon always faces the Earth. The motions of the moon can be observed through events such as phases of the moon, tides and eclipses. Actual Motions of the Moon
Phases of the Moon Half the moon is always receiving light from the Sun. The varying amounts of the “lighted moon” as seen from Earth are known as moon phases.
Tides The cyclical rise and fall of ocean waters as a result of the gravitational attractions between the Earth, moon and Sun are known as tides. The moon has a much greater impact on the tidal patterns of Earth due to its close proximity to the Earth. A high tide on Earth is created when the Earth is directly under the moon. Another high tide would be exhibited on the opposite side of the Earth as the solid mass of our planet is pulled towards the moon. The result is another high tide. Twice per day A low tide on Earth is created when the Earth is 90° from where it is directly under the moon. The gravitational attraction between the Earth and the moon is at its lowest. Twice per day
Tides The Earth experiences higher high tides and lower low tides when the Sun, Earth and moon are along the same straight line. This is due to the gravitational attraction of the Sun and moon upon the Earth. Thus the tidal effects would be more extreme. Spring Tide Neap Tide Neap Tide Spring Tide
Eclipses An eclipse is when a celestial body partly or completely comes into the shadow of another celestial body. Lunar Eclipse Solar Eclipse
A lunar eclipse occurs when the Earth casts its shadow (partially or completely) on the moon. A lunar eclipse would occur when the moon is in its “full moon phase”. When a total lunar eclipse occurs, all people should be able to view the eclipse in the night sky. This is because the shadow of the Earth (umbra) is larger than the moon itself. Lunar Eclipse
A solar eclipse occurs when the moon (partially or completely) blocks the Sun casting a shadow upon the Earth. A solar eclipse would occur when the moon is in its “new moon phase”. When a total solar eclipse occurs, only a few people would be able to view the entire eclipse in the daylight sky. This is because the shadow of the moon (umbra) upon the Earth is quite small and would been seen for a short period of time along a specific path along the Earth’s surface. Solar Eclipse