Lunar Cycles

Mankind has been observing the various stages of lunar cycles since time immemorial. One of the most interesting phenomena of nature that has fascinated all of us in our childhood days, is the sight of the ever-changing appearances of the moon. Moreover, Full moon on a clear sky captures the imagination of several poets.

Basic Facts about Lunar Cycles

We all know the fact that the moon is the satellite of the Earth and it revolves around the Earth in an elliptical path. It takes approximately 29.5 days to complete one lunar cycle. Due to the elliptical shape of its orbit, the angular distance between the moon and the Earth changes from time to time. Half of the moon remains lit by sunlight all the time. To an observer on Earth, this bright part of the moon is visible in changing angles due to its rotation round the Earth in its oval-shaped orbit. These changing angles are mainly responsible for the changing appearances of the moon or the lunar cycles.

Main Phases of Lunar Cycle

The main phases of a lunar cycle or lunation can be divided into nine categories. The sequence of the lunar cycles are as follows:

1. New Moon - During the new moon phase, the sun, moon and Earth are present in the same line. The moon is placed in between the Earth and the sun. So the illuminated hemisphere of the moon becomes invisible to an observer on the Earth.
2. Waxing Crescent - It is the phase when a New Moon starts drifting to next Full Moon. During this phase the moon is visible only between sunset and midnight.
3. The First Quarter - Here the moon is perpendicular with respect to both the sun and the Earth. In this phase, the sunlit portion of the moon is in an increasing mode.
4. Waxing Gibbous - It's the phase falling in between the First Quarter and the Full Moon and its duration is of seven days. Here the moon is illuminated from right to left. This moon is visible after sunset and it disappears just before the sunrise.
5. Full Moon - During the full moon, the sun, moon and Earth are aligned in a straight line. The moon is positioned opposite to the Earth as a result of which the portion of the moon illuminated by sunlight is visible to us.
6. Waning Gibbous - It describes the Moon that is shrinking to a smaller size. During this period, the moon is lit from left to right. This moon can be seen by joggers and morning walkers early in the morning as it sets after sunrise.
7. The Third Quarter - This Quarter comes after the Full Moon phase, when the sun partially lights up the moon. But in this phase, the illumined portion of the moon reduces to half of its size in the full moon phase.
8. Waning Crescent - In this phase, only a thin slice of the moon is visible and that too, not before midnight.
9. New Moon - Here, the moon starts a new journey all over again.

Researchers and scientists believe that lunar cycles have an effect on sea tides and may cause some climatic changes. Apart from the scientific observations, lunar cycles are also closely watched by astrologers, who believe that lunar cycles are mainly responsible for the way men and women react to a particular situation at a given point of time.

As long as our planet exists, people will keep researching and continue to fantasize on this wonderful phenomenon of the night sky called lunar cycle.