Fact Check: The Great Wall of China is visible from space

Fact-Check: "The Great Wall of China is visible from space"

What We Know

The claim that the Great Wall of China is visible from space has been widely circulated and is often considered a myth. According to Norberto López-Gil, who analyzed the visibility of the Great Wall, even the best human eyes cannot see it from space due to its narrow width (typically less than 6 meters) compared to its length (over 13,000 miles). The human eye's limitations in visual acuity mean that small objects, like the Great Wall, become indistinguishable from the surrounding landscape at significant distances.

This assertion is supported by NASA, which states that the Great Wall is not visible from the moon and is difficult to see from Earth orbit without high-powered lenses. Additionally, Yang Liwei, China's first astronaut, confirmed that he could not see the Great Wall during his space mission, further debunking the myth.

The idea that the Great Wall is visible from space has historical roots, with references dating back to the mid-18th century. A letter by William Stukeley suggested that the wall could be discerned from the moon, a notion that has persisted over time despite being scientifically disproven.

Analysis

The evidence against the claim is robust and comes from multiple credible sources. López-Gil's analysis highlights the physical limitations of human vision, stating that even under optimal conditions, the Great Wall would appear as a thin line, akin to a human hair when viewed from a height of several kilometers. This conclusion is corroborated by Scientific American, which emphasizes that reports of astronauts seeing the Great Wall are exaggerated.

NASA's findings also reinforce this perspective, noting that while images of the Great Wall can be captured from space using advanced technology, it remains largely invisible to the naked eye from orbit (NASA). Furthermore, Snopes and Sky at Night Magazine confirm that the Great Wall is almost invisible from altitudes as low as 180 miles, which is significantly closer than the distance to the moon.

The reliability of these sources is high. NASA is a reputable space agency with a long history of scientific research, while López-Gil's work is published in a peer-reviewed context. Scientific American is a well-respected publication in the field of science communication, and Snopes is known for its fact-checking rigor.

Conclusion

The claim that "The Great Wall of China is visible from space" is False. The evidence clearly indicates that the Great Wall's narrow width and the limitations of human visual acuity make it impossible to see from space without the aid of high-powered lenses. Both historical assertions and modern scientific findings support this conclusion, demonstrating that the myth has been debunked by credible sources.

Fact Check: The Great Wall of China is visible from space