With this simple device, you can measure the motion of the stars!

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Glue the quadrant template to a piece of cardboard, then cut it out.

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Tape a straw to the top edge of the quadrant, over the darker stripe on the template. Make sure it's straight!

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Use a pencil to poke a hole through the circle in the corner of the quadrant.

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Poke one end of the string through the hole and tape it down on the back side.

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Tie or tape the weight to the other end of the string.

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Here's how to use your quadrant to find the latitude of your house. You'll need a clear night and a place you can see the stars.

1. Start by finding the Big Dipper. Draw an imaginary line between the two outer stars of the bowl part of the dipper. Follow that line to find the North Star.

2. Close one eye and look through your straw up at the North Star. When you have it in sight, have a friend write down the number the string is hanging over.

3. Take the reading two more times. Then add the three numbers together, and divide by three. This number is your latitude!

• ## Step 8

You can also use your quadrant to measure the motion of the stars over the course of a night, or throughout the year.