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I'm not lost . . . I've got a map!

Seeing Through Different Eyes | What is an image? | I'm not lost . . . I've got a map!
So what if the Earth is round?! | A new wrinkle . . . the third dimension. | Earth vs. the Center of the Galaxy




When was the last time you got lost and had no idea where you were?

How did you ever find your way to your destination? You probably followed a simple series of steps.

1. You need to find out where you are. To do this, you take note of your surroundings. For instance, say you were lost somewhere in New Jersey. You can see some mountains where you are and  road signs that you are somewhere around Newton near Route 206, but you need to be in Hopatcong. Well, at least you know your starting point...Newton. This is what we would call an ORIGIN

2. You look at your map and see you need to travel southeast from your current position. You just defined a COORDINATE SYSTEM or a direction on the map in which up is north and left is west.

3. You look at the inset on the map and figure out how far you are from your destination. For instance, one inch might equal 20 miles. The inset defines a SCALE LENGTH. It tells you how far you have to go.

check list Let's quickly review the three things we needed to define in order to get from Newton to Hopatcong.
  1. Origin
  2. Coordinate System or direction
  3. Scale Length  or distance


THE PIRATE'S TREASURE

Now, imagine you are a pirate in search of buried treasure and all you have is a map. Take a minute to describe how you would find the treasure using the map.
  • Did you have a starting point (an origin)?
  • Did you use terms like up/down or west/east (coordinate system)?
  • Did say you needed to travel a certain distance such as 3 miles west then 2 miles south to the mountains (scale length)?
  • How could you find out what the scale length was, if it wasn't shown on the map??
That was easy, wasn't it? Do you think it would be harder to find your way from New Jersey to Austrailia? Of course not. All you need are an origin, coordinate system and scale length. The Earth and its maps can already provide you with all three. Let's check it out.
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