Astronomy Myth #5 – The Great Wall of China is visible from space

Nothing could be further from the truth, because an object has to 70 miles (112.6 km) across if you wanted to see it from the surface of the Moon without optical aid. Astronaut Alan Bean, who was on the Moon during the Apollo 12 mission, describes how Earth looks from the Moon- “The only thing you can see from the Moon is a beautiful sphere, mostly white, some blue and patches of yellow, and every once in a while some green vegetation. No man-made object is visible at this scale.”

So, even though the Great Wall is more than 5 000 miles long, it is only 30 feet (9.1 m) wide at its widest point, which renders it invisible to the naked eye, even from the International Space Station, which is no more than 220 miles or so above the earth. It is however possible to see some large dams and bridges from the ISS, but the Great Wall of China? Not a chance.