# Science Projects for Kids: Measuring

Lifestyle | Other Arts & Crafts

Use the North Star to find your latitude.

You can use the North Star to find your latitude. Try this science project for kids, and you'll be using the same technique that the ancient Greeks did.

Long before our modern navigation systems were developed, people in ancient times navigated by the stars. The ancient Greeks knew the world was round and invented a system we still use to map and measure the globe. They divided the globe into latitude lines based upon the apparent altitude of the north star above the horizon. To find your own latitude, you'll need to outdoors on a clear night and look for the North Star.

### What You'll Need:

• Protractor
• String
• Key

Step 1: Find the North Star on a clear night.

Step 2: Tie a key or other weight to one end of a piece of string and the other end to the cross bar of a protractor.

Step 3: Turn the protractor so that the curved edge faces downward. Tilt it so that the string hangs exactly at "zero."

Step 4: Slowly tilt the protractor, and look along the straight edge until you can see the North Star. Notice which degree mark the string now crosses. This indicates how many degrees above the horizon the North Star is. This figure is also your degree of latitude.

### Star's Altitude Above the Horizon

You can measure the altitude above the horizon of any star using the same technique, but latitude lines are based only on the angle of the North Star. Try using your fingers instead.

If you hold your hand out at arm's length, each of your fingers is approximately four degrees wide. Your hand minus the thumb (four finger widths) is usually 15 to 16 degrees. All hands and arms are not alike, however, so use the protractor to check any measurement you make this way.

Who needs a ruler when you have a box of paper clips? Look on the next page to try this system of measurement.