Understanding the Moon

What creates the moon phases?

The phases of the moon refer to the moon's continuous orbit around the earth. As the moon orbits the earth, the phases change and it gives us an indication of the moon's progress in the cycle. The sun always illuminates exactly one-half of the moon, but we see it at different angles as it rotates around the earth. With the naked eye, we can see only the part of the moon that the sun is illuminating. For instance, a crescent moon is what we call the moon when we see only a small portion of its illuminated surface.

What are the phases of the moon?

1.     New (also called the Dark Moon) - not visible

2.     Waxing Crescent

3.     First Quarter - commonly called a "half-moon"

4.     Waxing Gibbous

5.     Full - we can see the entire illuminated portion of the moon

6.     Waning Gibbous

7.     Third Quarter - another "half-moon opposite of the First Quarter

8.     Waning Crescent

9.     New - back to the beginning

Why does the moon rise and set different times during the day?

Due to earth's rotation, the sun and the moon are rising and setting. With a Full Moon, the moon is opposite to the sun; when the sun sets the full moon rises, and when the sun rises the full moon sets. New Moon means the moon is almost riding together with the sun, so the rising and setting times are almost the same. First quarter moon stands left of the sun, so it will set many hours after the sun has set. And a last quarter moon stands right of the sun, so it will already been risen many hours before the sun will rise.

Growing or Shrinking? How can you tell?

If you want to determine if the moon is waxing or waning all you have to do is look when you can see it. If it is visible in the evening sky the moon is waxing. If the moon is visible at dawn or in the early morning, it is waning. Here is a rhyme to help you remember it.

If you see the Moon at the end of the day

A bright Full Moon is on its way

If you see the Moon in the early dawn

Look real quick, it will soon be gone.

            Another way to identify a waxing or waning moon is to look at which side is "incomplete". When the moon is illuminated in such a way that the side facing West is "incomplete" the moon is waning. If the side to the East is "incomplete" the moon is waxing.

Incomplete to the West

The Moon will disappear and hide in its nest

Incomplete to the East

Soon it’s as big as a Christmas feast.