orbit (n,vb) revolve (vb) / revolution (n)
phase (n) reflect (vb) / reflection (n)
o The moon orbits the earth.
(The moon goes around the earth. Another word for "orbit" is "revolve" or "revolution.")
o It takes 27.3 days for the moon to revolve around the earth.
o The moon does not make its own light. It is not like the sun, which produces light.
o The moon "shines" because it is reflecting the light from the sun.
o When we see the moon in the sky, we are seeing the parts of the moon that are reflecting light from the sun.
o Half of the moon is always reflecting light from the sun. However, we cannot always see that side from Earth.
o As the moon moves around the earth, how much of the moon we can see changes. The word we use to talk about "how much moon we see" is "phase."
(The word "phase" means "stage," but the moon doesn't really go through stages. The moon doesn't change - just how much we can see changes.)
o When the earth is between the moon and the sun, the moon looks like a bright circle because we can see the whole side that is reflecting the sun. This phase is called "full moon."
o The names for the eight main phases of the moon are:
www.space.com
This is what we see
This is what the moon looks like from new moon to new moon.
Try to pick out the different phases and say the names while the picture is moving.
Reproduced with kind permission of Ed Stephan
It takes 27.3 days for the moon to orbit the earth.
BUT it takes 29.5 days to go from new moon to new moon.
Why? Think about it and see if you can figure out the answer.
Click here to find out the answer and for other interesting information about the moon.