Greatest Places: Activities: Mapping in the Round

A C T I V I T I E S

Imagine an orange as a model of the earth.

Wash it with soap and water to remove any waxy coating. Roll the orange on a table top with the flat of your hand to loosen the peel. Take the orange and put a flat rubber band around the middle of it, covering the stem and the navel. Now the orange is divided, into equal halves. Take another rubber band and put it around the middle of the orange the other way, exactly halfway between the stem and the navel. The first rubber band represents the prime meridian; the second rubber band represents the equator. Mark along each line with a marker, or scratch along each line with a straightened paper clip or a fingernail. (Markers can be a little messy). Remove the rubber bands after you have traced both circles on the orange.

The first circle you traced is the prime meridian, an imaginary line which goes through the North Pole, England, western Africa and the South Pole. Using a globe for reference, find and mark (or scratch) the approximate centers for each of these land masses on the orange, using the lines you marked as guidelines. (e.g. What part of Africa is above the equator? About how far would it go south of the equator on your orange? What parts of Africa are west of the prime meridian?) Find and mark the centers of other continents in the same way. (Where is South America in relation to Africa and the equator?) Working out from the center, scribble or scrape the rough shape of all the continents on the surface of the orange. Don't worry about doing it perfectly and don't try to draw outlines; it's almost impossible to draw them accurately. Scribble in the shapes instead and concentrate on where places are in relation to each other.

When you are done, carefully cut through the line around the equator with a plastic knife or a paper clip, without cutting the orange underneath. Carefully slide your finger between the peel and the orange segments to completely separate them. Now slowly remove the two hemispheres of your orange without breaking any of the peel. (You may need help with this.) The lines between orange segments, running parallel to the prime meridian and perpendicular to the equator, represent lines of longitude. You can eat the areas between these lines.

Place the two half globes, or hemispheres, on the table with the continents facing up. If you wanted to have flat maps like those in a book, the continents would have to be flat. What do you have to do to make the 3D contintents into flat, 2D maps? Go ahead and flatten them. What happens?

See how other people map the world...