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Space, GPS & MapsMyth-busting

You Can't See the Great Wall From Space

The famous claim is a myth

Everyone knows you can see the Great Wall from space. So why do astronauts keep looking for it and coming up empty?

You'll find out

  • What a sharp eye can and can't pick out
  • Why a highway beats the wall
  • How old the famous claim really is

Why it matters

Whether you can see a thing depends on its width and its contrast. The same rule limits cameras, telescopes and screens.

About 3 min6 interactive slides · 5 questionsLesson 136 · Zone 16

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