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Spaceship Earth Unit
Why does the Moon change shape?
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DISCUSS:
What do you notice about the Moon each night? (1 of 14)

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DISCUSS:
What do you notice about the Moon each night? (2 of 14)

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DISCUSS:
What do you notice about the Moon each night? (3 of 14)

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DISCUSS:
What do you notice about the Moon each night? (4 of 14)

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DISCUSS:
What do you notice about the Moon each night? (5 of 14)

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DISCUSS:
What do you notice about the Moon each night? (6 of 14)

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DISCUSS:
What do you notice about the Moon each night? (7 of 14)

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DISCUSS:
What do you notice about the Moon each night? (8 of 14)

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DISCUSS:
What do you notice about the Moon each night? (9 of 14)

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DISCUSS:
What do you notice about the Moon each night? (10 of 14)

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DISCUSS:
What do you notice about the Moon each night? (11 of 14)

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DISCUSS:
What do you notice about the Moon each night? (12 of 14)

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DISCUSS:
What do you notice about the Moon each night? (13 of 14)

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DISCUSS:
What do you notice about the Moon each night? (14 of 14)

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DISCUSS:

Before you start the activity, discuss as a class: what ideas do you plan to test to see if you can create the Moon’s phases and make them go in order?

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Check out the video in the next slide to see your Moon phase model compared side-by-side with the real sky!

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DISCUSS:

Now that you've learned what causes the Moon's phases, how would you explain it to someone who doesn't know?

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You've completed the Exploration & Activity!

If you have more time, view the assessment, reading, and extension activity in the extensions.

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Extensions

Below are ideas for extending this topic beyond the activity & exploration which you just completed.
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Activity: The Moon's Face

Encourage creative storytelling by asking your students to look for pictures on the Moon's face using this activity from the Lunar and Planetary Institute. For photos showing what various cultures have seen on the moon, check out this National Geographic article

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Animation: The Phases of a Tree

Ordinary objects have phases, like the phases of the moon. But usually we don't even notice these changes in lighting.

You and your class can see how this works at Dr. Cecilia Barnbaum’s Astronomy Demo Site. Click on "Moon Phases" to see the phases of a tree and a ball in the sunlight.

Hit the play button to start the animation. There is no narration, so we suggest you pause to talk with your class about what the animation is showing. When is the tree a "crescent tree"? When is it a "half tree"? Watch the animation all the way through to see all the phases.

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Image & Video Credits

Mystery Science respects the intellectual property rights of the owners of visual assets. We make every effort to use images and videos under appropriate licenses from the owner or by reaching out to the owner to get explicit permission. If you are the owner of a visual and believe we are using it without permission, please contact us—we will reply promptly and make things right.

Exploration
Venus & the Moon by Claude.schneider , used under CC BY-SA / cropped, adjusted color, added border
moon rising by flowcomm , used under CC BY / cropped, adjusted saturation, layered with another image
reaching for the moon by Sivaprasad k S / spliced
full moon by Krückstock , used under CC BY-SA / adjusted saturation
harvest moon rising by slworking2 , used under CC BY / adjusted color and speed
moon in daylight by Zeynel Cebeci , used under CC BY-SA / adjusted color and cropped
moon in sky by Bill Johnston / cropped, layered with other imagery
crescent gibbous moon by Thomas Bresson , used under CC BY / Heavily modified
crescent moon by P. Bramwell / Heavily modified
moon view by Luc Viatour , used under CC BY-SA / Heavily modified
house at night by StruffelProductions / cropped
sunrise background by Stellarium / Heavily modified
tablet by simon-ho / Heavily modified
lightbulb by KMJ , used under CC BY-SA / Heavily modified
Earth by Celestia / part of a diagram
Other
crescent moon by Richard Flink , used under CC BY-SA / cropped, adjusted color
Overview
Grade 5th
Topic Sun, Moon, Stars, & Planets
Focus Moon Phases, Lunar Cycle
Print Prep
Activity Prep

This Mystery explores why the Moon seems to change shape (phases) over the course of a month. In the activity, Model the Moon's Phases, students use a styrofoam ball as a model of the Moon and a flashlight as a model of the Sun to gain a better understanding of how the interactions between the Sun and Moon are responsible for the Moon’s phases.

Preview activity

Number of students:
Pencil
Sharpened. Skewers also work.
Details
15 pencils
Bright Flashlights
You can also use a bright lamp or overhead projector that you can point towards the students to serve as the Sun for multiple groups. Be careful not to look directly into such a bright light source.
Details
15 flashlights
Styrofoam Balls (2")
We suggest smooth, solid styrofoam balls. Rough foam balls are translucent and don't work as well. You can substitute any round opaque object that can be skewered.
Details
15 balls
Prep Instructions

We suggest students work in pairs. Homeschool students will need a partner for this activity.

Prepare to Darken the Room

It is important to get your room as dark as possible! It's worth taking the time to black out your windows and even tape curtains to eliminate cracks of light. Also, the brighter your flashlights, the better the demonstration. The flashlights we link to are particularly bright and inexpensive.

Overview
Grade 5th
Topic Sun, Moon, Stars, & Planets
Focus Moon Phases, Lunar Cycle
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