I remember being told this in high school and being totally confused. My teacher told us that a standard map, or even a globe, is inaccurate. She explained why but I didn’t understand. Why is this?
In: Technology
Imagine you have a balloon and you draw a bunch of same sized dots on it, then you cut a line to define one edge of the balloon and and try to lay it flat like a map. Obviously, you’re going to have trouble simply making it lie flat without tearing or folding (it’s actually impossible to make spheres lie perfectly flat this way), but those dots will also lose some of their clarity, getting bunched up or pulled apart. Considering the stuff where the dots would be on a globe is all of the Earth’s geography, this is a problem.
The most common map in the world gets around this problem by making the dots (ie: the land), at the top and bottom larger to account for the stretching, but this does distort distances (although, conveniently, it means that if you move in a straight line on the map, you also move in a straight line in real life, which is why it was used by so many people). Other maps get around this by stretching or squashing the dots. Each method has its upsides and downsides, but none can perfectly capture all of the information a globe provides at the same time.
Globes are very close to the true shape of the Earth, however the Earth is both slightly flatter than you would think, and also more lumpy. That said, the issues with a globe are much smaller than the issues with any map. You can generally rely on their accuracy.
An example of the dots (known to map makers as a **Tissot indicatrix**) with the most common (Mercator) type of map can be seen below. On a globe, all of the red dots would be the same size:
[https://upload.wikimedia.org/wikipedia/commons/8/87/Tissot_mercator.png](https://upload.wikimedia.org/wikipedia/commons/8/87/Tissot_mercator.png)
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