I was listening to the Breakfast Show the other day and in his tedious link Dave said you could see the Great Wall of China from space. A barage of texts got sent in saying, "You can't see it from space you idiot!" and "You can see it from orbit". So then I got really confused, because I backed Dave and always thought you could see it from space. Following this, Corinne said you could see if from orbit and Lucy said it's a common myth but you can't. This was about three days ago and I am still confused over the matter. Can you or can't you?

According to About.com, from a low orbit many artificial objects are visible on the earth, like ships in the sea, railways, cities and even individual buildings. So, yes you can see the Great Wall of China from low orbit but it's not unique in that respect. It goes on to say that when you leave the earth's orbit, no man-made objects are visible. Apparently NASA say, "The Great Wall can barely be seen from the Shuttle, so it would not be possible to see it from the Moon with the naked eye."

An article in The Guardian details Yang Liwei, China's first man in space who came back to Earth to reveal that he hadn't seen the Great Wall, a comment that some took as proof that it was a myth. Yet it is possible to see man-made structures a couple of miles up in space. Ed Lu, had been living on the international space station since April that year; the article was written October 2003. "It turns out you can see an awful lot from space," Lu says on Nasa's website. "You can see the Great Wall. I've been trying, thus far unsuccessfully, to take a nice picture of it."
Nobody at Nasa knows where the the whole idea came from, but it was doing the rounds before the first satellite was launched.

So basically, yes you can see it, but only from a low orbit along with other man-made structures. Glad that's sorted, I can sleep properly now...