Some myths start off as speculation and grow completely out of hand. This one seems right up that ally. And not just students, but many adults also think that the Great Wall of China is visible from the Moon. There have also been claims that it is the only man made structure visible from space. Even after repeated articles clearing this aspect, the myth refuses to clear up. So here is another explanation of the possibility or impossibility of seeing the Great Wall of China from the Moon.
To begin with, the Great Wall isn’t a continuous stretch but an array of short walls that extend over 2400 kilometers. In addition, these short walls are approximately seven and a half meters high and just about 4 meters wide at the top. Thus, they aren’t even as tall as a typical skyscraper. It does extend over an extremely large distance, but there is no reason for it to be visible from space if its barely 4 meters wide. Most of us would have noticed that from a hill or a mountain, when looking down into a city, it is almost impossible to resolve (clearly identify) individual buildings. If that is the effect a small mountain has, imagine how difficult it will be to see any structure from the moon. In fact from the Moon, even continents are barely visible.
No one claims to be able to see the huge ridges formed along the boundaries of craters of our Moon when in fact they are bigger and larger than the Great Wall of China. And since you cant see structure on the Moon from Earth (except with a telescope), there is no way to see structure on Earth from the Moon.
Of course, from a low Earth orbit, this Wall will be visible but from that distance you can also see large highways and perhaps individual skyscrapers. So the sight of the Great Wall of China wouldn’t be unique.
As far as the origin of this myth is concerned, some believe that it started as a speculation by some big-shot during an after-dinner speech in the early days of the space program but be assured that the this wall cannot be seen from the Moon.
The Great Wall of China is definately long, but not tall enough or wide enough to be visible from the moon
Nikhil Pawar
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Posted on March 12, 2008
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