It’s commonly said that the Great Wall of China is the only man-made structure that can be seen with the naked eye from space or the moon . This proposition has been per-
petuated in many sources: it’s a question in the board game Trivial Pursuit, it has been contained in schoolbooks across the world and it was stated as being the case by Ed Harris in the 1998 movie The Truman Show . In addition, Richard Halliburton’s Second Book of Marvels makes such a claim, despite the fact that this book was first published in 1938, before man launched any satellites!
One school of thought is that the claim was made to convey the enormous scale of the Wall and the vastness of man’s achievement in building it . It is now accepted that the proposition is false .
Many large-scale Man-made objects, such as highways, airports, buildings and ships, can be seen with the naked eye, as can the Great Wall itself, but only from low Earth orbit (up to about 200 miles above sea level) . The Wall’s width ranges from about five to ten meters but, when dust storms hit it, it becomes more visible at this close range .However, no man-made structures at all are visible with the naked eye above an altitude of a few thousand miles, and certainly not from the moon, which is about 240,000 miles away and from which entire continents and oceans are barely visible without mechanical assistance . These facts have been con-firmed by a number of astronauts who have left the question beyond any doubt .
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