1. Phases of the Moon

2. The moon rotates at the same rate it revolves.
Rotation
The moon also rotates.
The moon rotates at the same rate it revolves.
What is the daily movement of the Earth called?
Because of this, we never see the far side of the moon.
If we always see the same side, why does the moon look different during the month?

3. The new moon occurs when the moon is between the Earth and the sun.
During a new moon the side of the moon facing the Earth is not reflecting any sunlight. It appears as if there is no moon at all.
The new moon occurs when the moon is between the Earth and the sun.

4. The new moon is the beginning of the cycle of lunar phases.

5. As the moon continues to travel along its orbit, we are able to see only a small portion of the moon. This is called a crescent moon.
Waxing means growing. Since the moon appears to be growing this phase is called waxing crescent.

6. As the moon continues to revolve around the Earth, we are able to view more of the lighted side of the moon.

7. In essence we are only seeing half of the lighted half of the moon.
Why is it called a quarter moon when it appears that we are seeing half the moon?
Remember we are not seeing the dark side of the moon.
The next lunar phase is the first quarter moon.
Half of a half is a quarter!
1/2 X 1/2 = 1/4

8. Do you remember what the word waxing meant?
As the moon begins to “grow” into a full circle it is called a waxing gibbous.
The word gibbous means swollen on one side.
Waxing means growing!

9. The full moon is the next lunar phase.

10. When a full moon occurs the Earth is between the sun and the moon.
During a full moon we see a complete circle in the sky, even though only half of the sphere is reflecting sunlight.

11. During the waning gibbous phase the moon seems to be disappearing!
Waning means shrinking.
The next phase is called waning gibbous.
What does gibbous mean?
Swollen on one side.

12. Why is it called a quarter? The last quarter is the next lunar phase.
Remember we are seeing half of a half or one quarter of the whole moon!
The last quarter is the next lunar phase.

13. They are mirror images of each other.
How is the last quarter moon different from ...
the first quarter moon?

14. Waning means shrinking. You are seeing a smaller portion of the moon.
What do you think the next phase is?
The last phase is the waning crescent.
What does waning mean?

15. The new moon!

16. The complete lunar cycle takes about 29 days.

17. The moon is not really blue. Two full moons in one month rarely appear.
When two full moons occur in the same month, the second full moon is called a blue moon.
What is a blue moon?