Nicole Stott, via Universe Today
Which of mankind’s marvels can we actually spot from the final frontier? This question calls for a little perspective. Space is big. Sure, you might be able to gaze at the Amazon River while hovering a few hundred miles above sea level. But from the moon, you could barely even make out the continents! And our whole planet looks like nothing more than a dinky blue splotch from Mars’ surface. Still, astronauts traveling in Low Earth Orbit or on board the International Space Station can see quite a bit using nothing but their naked eyes.
1. The Great Pyramids at Giza
Some squinting may be required to spy Egypt’s greatest monuments in this picture snapped by astronaut Nicole Stott. If you’re really lost, look for a pair of triangular shadows near the center…
Chris Hadfield, via Huffington Post
Long bridges crossing over straits stick out like a sore thumb. However, identifying them can be a pain. Last year, astronaut Chris Hadfield caught a glimpse of what he thought was the Golden Gate, but may have really been a less-glamorous bay area counterpart.
3. Lonely Desert Roads
Chris Hadfield, via Universe Today
As Hadfield explains, desert highways look like “straight human [lines] drawn onto incredibly rough terrain," making them rather noticeable.
4. Cities at Night
Space-bound explorers have taken hundreds of nocturnal photos over various urban centers. Here’s a helpful interactive gallery. Go look up a metro area near you.
5. The Greenhouses of Almería
A sprawling sea of plastic greenhouses covers over 64,000 acres in southeastern Spain. Tons of fruits and veggies (tomatoes, cucumbers, peppers, etc.) are produced here, generating $1.5 billon in revenue every year.
Kinda, Sorta, Not Really Visible: The Great Wall of China
NASA, via Universe Today
Let’s get a few things straight. Can you see this ancient marvel while walking on the moon, as many claim? No way. Again, people really can’t see much of any detail Earth-wise from up there. On a similar note, it’s also effectively out of sight for the International Space Station’s crewmembers.
Another persistent rumor holds that China’s Great Wall is the only man-made structure that’s visible from space. As we’ve seen, this is nonsense. This demonstrably-false idea dates back to at least the 1930s, long before manned space missions started taking off!
Yet, one vitally important question remains: Where does space start anyway? By most international standards (even though a certain Air Force disagrees), the boundary between Earth’s jurisdiction and outer space rests approximately 62 miles above sea level.
From this height, the Great Wall is technically visible, at least according to astronauts Eugene Cernan and Ed Lu. However, it’s not exactly conspicuous. Even under the best solar and weather conditions, this landmark is virtually indistinguishable from neighboring rivers and mountains. Therefore, most space-travelers miss the Wall entirely.
In fact, one person who definitely didn’t see it was China’s first astronaut, Yang Liwei. “The scenery was very beautiful,” Liwei said after returning to Earth in 2003. “But I didn’t see the Great Wall.”