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Not many of you are likely to lie abed tonight pondering if it is really, truly possible to make out The Great Wall of China with the naked eye from space.

However, over the past few months the question has become politically electric in China, and in the process shed light on the nervousness with which all humanity views its uncertain place in the universe.

First, the background. Last October, Yang Liwei, China's first astronaut, announced a heresy. When looking down on earth from his rocket, he reported "the scenery was very beautiful, but I didn't see the Great Wall." This pronouncement flew in the face of what has long been a Chinese myth and national boast. Namely, that the five-to-10-metre-wide, 6,700-kilometre-long Great Wall was the only man-made subject that was visible with the naked eye from space.

Yang Liwei's observation led Chinese officials to demand that an apocryphal story about how an astronaut had seen The Great Wall from space be removed from all state textbooks. This caused the senior editor of the People's Education Press to defend his textbooks, declaring its critics were "fussy" and didn't understand the story's patriotic motives. "We want to help the students to be proud of their motherland and themselves as well. Our intentions are good," he told The China Daily.

The astronaut community soon split on the question of whether you can see the Great Wall from space. "I don't know who started that rumour," Canadian astronaut Chris Hadfield told a newspaper reporter. "It's in Trivial Pursuit. It's one of the answers, but it's wrong." The problem is less the wall's width than its colouration. "The Great Wall is dirt-coloured ... and camouflaged. But you can see the 401 (highway)," remarked Mr. Hadfield.

However, U.S. astronaut Eugene Cernan, the last person to walk on the moon, stirred the pot in a different direction in March. He told the Singapore Strait Times that "at Earth orbit of 160 kilometres to 320 kilometres high, the Great Wall is indeed visible to the naked eye...if you know where to look you can see the Astrodome in Houston, Tex., where I live."

Then three weeks ago the European Space Agency announced that its Proba satellite had been able to make out portions of The Great Wall as it cruised at a height of 600 kilometres above the Earth. Included in the announcement was an arresting image of the Great Wall supposedly meandering its way northeast of Beijing.

Scientists subsequently told British newspapers that they had been able to extrapolate from the clarity of the image Proba's cameras took that the wall should be visible to the naked eye at the lower edge of space – 100 kilometres up.

A week later, ESA announced a major-league "oops." "The feature that was claimed to be the Great Wall is actually a river running into the Miyun Reservoir," the agency wrote on its website, and then commented rather mysteriously "the errors arose because the image was not properly investigated prior to publication."

Gary Li, a professor of Geographic Information Systems at the California State University at Hayward, told me that ESA apparently made a fundamental interpretation error. They didn't flip the image 180 degrees and to see how the image would look if the sun were not shining at an angle, but more overhead as it is on earth. If they had "they would have seen the width of the line they imaged varied and the shading varied so you could see it was the shading you got from a river valley. And if you looked carefully you could also make out small houses on the river bank," said Prof. Li, who had sent a note to ESA about their faux pas after the first announcement was made.

So where does all this leave the seeing of the Great Wall of China from space issue? There is no doubt that satellites with special imaging capabilities can and have seen it. Indeed, in 1996, a NASA radar satellite was able to not only see the present wall but an older version of it that over the centuries had been buried by sand. It is also likely that with binoculars and an intense period of observation you can just about make it out – or so has claimed Chinese-American astronaut Ed Lu from his window seat on the International Space Station.

But ultimately who cares?

Our frail, collective human egos, I would suggest. The subtext of a Seeing-The-Great-Wall-From-Space-Dispute, is that if next to nothing we have made can be seen at what is barely a pipsqueak distance from the Earth, then we humans are a pipsqueak. But if something as old and legendarily awe inspiring as the Great Wall can be spied by a naked eye, well then we, in a collective sense, have a presence in the universe.

The psychological reality is that the cosmos is more and more frightening the farther as we get from Earth. You look back and there is nothing that says where we have come from. You look forward and there is nothing to say where we are going.

We are, when we have barely stepped on to our front porch space-wise, alone, and as a consequence all of us want grounding, be it Yang Liwei searching fruitlessly for the Great Wall, or Chris Hadfield purring inwardly that he's not backed up on the 401, or E.T. phoning up to announce:

"I've seen enough of Hollywood, now I want to see home."