The first lunar phase is called new moon. During this phase the moon is not visible in the northern or southern hemispheres. The second phase is called waxing crescent moon and it is the first time the moon is visible. During this phase 1 percent to 49 percent of the right side of the moon becomes visible in the northern hemisphere, and 1 percent to 49 percent of the left side becomes visible in the southern hemisphere. More of the moon becomes visible as time goes by.
The first quarter moon is the third lunar phase. Fifty percent of the right side becomes visible in the northern hemisphere, and 50 percent of the left side becomes visible in the southern hemisphere. The waxing gibbous moon phase is next, and 51 percent to 99 percent of the moon will be visible in the northern hemisphere, starting from the right side. In the southern hemisphere 51 percent to 99 percent will be visible from the left to right. More of the moon shows as time goes by.
The full moon is the next stage, and the entire moon is visible in both hemispheres. This is followed by the waning gibbous moon which allows for 99 percent to 51 percent of the left side to be visible in the northern hemisphere. In the southern hemisphere 99 percent to 51percent of the moon is visible starting from the right side. Less of the moon is visible as this stage progresses.
The last quarter or third quarter lunar phase is next. Fifty percent of the moon is visible in both hemispheres. It is the left 50 percent in the northern hemisphere, and the right 50 percent in the southern hemisphere. The waning crescent phase is next. In the northern hemisphere 49 percent to 1 percent of the left side will be visible. In the southern hemisphere 49 percent to 1 percent of the right side will be visible. The viewing area of the moon decreases during this stage.
The new moon phase is next and the entire cycle starts again. It normally takes about 29 days to complete a lunar cycle.