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Star Trails - Previous Version
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Check out this picture of the night sky.

DISCUSS: What do you notice? How would you describe the stars?

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This photograph captures a moment in time--maybe a second or two. The camera’s shutter opened and closed quickly, letting in a little light.

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Here’s another photo of the stars.

DISCUSS: What do you notice?

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To make a photo like this, the camera’s shutter stayed open for 3 hours. Check out this sped up video of a similar photo.
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Get a See-Think-Wonder chart to record your ideas.

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THINK-PAIR-SHARE:

  • What do you observe in this photo of the night sky?
  • Do you notice any patterns?

Record your answers in the SEE column of your chart.

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THINK-PAIR-SHARE:

  • Why do you think there are bright streaks in the sky, rather than stars?

Record your answers in the THINK column of your chart.

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THINK-PAIR-SHARE:

  • What else do you wonder about this picture?

Record your answers in the WONDER column of your chart.

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For thousands of years, astronomers have observed the night sky and tried to explain what they saw.

In this activity, you’ll start with this photo of the sky and figure out what causes the streaks you see. Like astronomers before you, you’ll create a model that helps you explain what you see in the sky. After each Mystery, you'll add to or change your model as you get new ideas.

We'll walk you through it, step by step.

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Reveal answer

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Reveal answer

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Reveal answer

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Reveal answer

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Reveal answer

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Reveal answer

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Conceptual Model

Models are used by scientists to understand and explain something. A model is revised, or changed, as new information is learned.

There are many types of models, but you just finished creating a conceptual model.

A conceptual model helps scientists explain things that they can't see. After each Mystery, you will add the new things you've learned to your model.

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You've completed the Unit Starter!

Be sure to keep each student's Star Trails Model accessible. They will use it after each Mystery in the Unit Connection.

Teach Mystery 1 next: How fast does the Earth spin?

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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.

Other
Ferris wheel by Pablo77
Fire Spinner by Wandee007
Helicopter by Journey601
Highway light streaks by Ure
Perseids at MaryHill Stonehenge by Nikky Stephen
Photographer and stars by Luck Luckyfarm
Sparkler smiley face by Pavel L Photo
Star Trail video by Naotharp
Print Prep
Activity Prep

The Unit Starter introduces the unit anchoring phenomenon, star trails. Students generate observations and questions about the phenomenon and create an initial model to explain what causes these patterns to form.

Preview activity

Before starting this lesson, review the unit Teacher Guide which gives an overview of the Spaceship Earth Anchor Layer.

In the Unit Starter, students are introduced to the unit anchoring phenomenon, star trails photography. In the activity, they create an initial conceptual model to explain how the star trails patterns are created. Students will re-visit their model after each Mystery to add new information to it.

It is important to encourage students to recognize that even if they don't know the full answer yet, they are going to learn a lot throughout the unit to help them explain the phenomenon and that they'll have an opportunity to change or add to their first model.

Step 1: Set up your classroom Set up your classroom by creating a class "See-Think-Wonder" chart (the student version is linked below). We recommend using chart paper, or a space on your board that won't be erased since you will revisit it throughout the unit.

Step 2: Print out worksheets Each student needs a:

Extensions
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