Map Projections

Make a map of the Earth

1. Cut off the top of a soda bottle where the bottle straightens. Cut off the skinny neck of the bottle without slicing through the "globe."

2. Draw lines of latitude and longitude on the inside of the globe. Doing this will be easier using a bowl or some other round object to guide the marker.

3. To represent a planar projection, place the globe on a piece of tracing paper. Hold the flashlight above the globe and shine its light down through the globe and onto the tracing paper. Draw the lines of latitude and longitude as they are projected on the paper.

4. For a cylindrical projection, roll the tracing paper into a cylinder the diameter of the globe. Shine the flashlight through the globe and onto the tracing paper. Draw the lines of latitude and longitude as they are projected onto the paper.

5. A conical projection is a compromise between planar and cylindrical projections. Make a cone out of the tracing paper and rest it on top of the globe.

6. Shine the flashlight through the globe and into the cone. Draw the lines of latitude and longitude as they are projected onto the cone.

7. Discuss alternative map-making methods that would minimize the distortions inherent in maps.

Materials

clear plastic soda bottle, flashlight, tracing paper, scissors, marker, pen