Moon Phases

Student Planet Facts

Watch the Moon phases The Moon looks different every night. As the moon orbits (moves around) the Earth, the sun's light reflects off of the moon. You can see the moon change over a month in the animation at left from NASA (Credit: António Cidadão). Notice how the moon gets closer and farther away. Learn more about the phases of the moon and when you are ready, click back to return to Explore the Moon or click below to explore somewhere else. See also Craters and Eclipses.

Moon Phase Quiz

Look at the pictures below. Each one has a sunlit side and some have a side in shadow. See if you can put them in order by writing down the shapes in the upper left corners. The answer is at the bottom of this page.

Solid Square	Round	Small Dot	Empty Square	Clover

Model the Earth-Moon-Sun System

Try this to help you decide the order. Place a lamp (as the Sun) in the center of the room. Have a ball (representing the moon) in your left hand stretched out in front of you. Pretend your head is the Earth and that you are standing on the tip of your nose. Turn the lamp on and turn out any other lights.

New Moon
Hold the ball between you and above the lamp and you will see just shadow on the ball. This lunar phase is called New Moon. When the ball blocks out the light from the lamp it is called an eclipse which only happens once in a while. Spin slowly to your left and watch as the lamp starts to light up the ball. This is called a Waxing Crescent Moon. Which side is lit first?

First Quarter Moon
When half of the ball is lit you are at First Quarter Moon. A Waxing Gibbous Moon is between First Quarter and Full. Waxing is a term meaning "getting larger".

Full Moon
Continue to move counterclockwise (spinning left) until your back is to the lamp and the ball is fully lit. You may have to hold the ball just above your head to see this. This is called a Full Moon. A Waning Gibbous Moon is between Full and Third Quarter Moon.

Third Quarter Moon
As you keep turning you will see Third Quarter Moon. Which side is lit now? As you turn finally to a Waning Crescent Moon then the cycle starts all over again at New Moon. Waning is a term meaning "getting smaller".

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Try this out...

What was the phase of the moon on your birthday, your friend's birthday or a holiday?
To find out, click here to open a new window to go to the US Naval Observatory:
Virtual Reality Moon Phase page.

Moon Phase Calculator

The box below shows what the moon looks like at the current time and when the next phases will be. The "age" of the moon is based on how many days, hours and minutes have passed since new moon. Make a sketch of the current lunar phase so when you are outside you can compare it with the moon. You can also mark your calendar and check to see if the moon matches the drawing on that day. The times for the phases are given in Universal Time. For example, for Pacific time you will need to subtract 8 hours (7 hours Daylight Savings time) from the time listed.
(For information about the author of this lunar phase calculator click the world icon, but you must use your back button to return to Kid's Cosmos.)

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Find out more about the moon by clicking on the images below.


Full Moon Lore	Craters	Eclipses

These links will take you to another website by opening a new window.
Close the window to return to Kid's Cosmos.

Click image for moon exploration website.

The Nine Planets
More Moon Facts
NASA Planet Facts
Moon Exploration History

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Answer: Clover (Waxing Crescent), Solid Square (First Quarter), Round (Full), Empty Square (Third Quarter), Small Dot (Waning Crescent)

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