Phases of the moon

The phases of the moon are the different appearances of the moon that result from the moon changing position in relation to both the earth and the sun.

In that regard, the moon which is the earth’s satellite, takes approximately twenty-eight days (one month) to complete one rotation of its axis as well as to revolve once around the earth. As a result, the moon always faces us with the same side.

Since the moon is non-luminous and it only reflects light coming from the sun, the side of the moon facing the sun will be illuminated while the other side will be in shadow. This is indicated by the inner set of the diagram below.

As the moon continues to rotate on its axis and revolve around the earth, it appears to change in shape. The outer shape of the drawings indicates what these changes look like at different times in the month and why they occur.

These are known as “phases of the moon” and they are result of the moon changing position in relation to both the earth and the sun.