I love astronaut photography of Earth, especially the dizzying and psychedelic time-lapse videos. I’ve wondered, though, why we don’t see more straight-up plain old video of the Earth as the International Space Station passes over?
It’s fun to see places I’ve visited (or even lived, like Houston and San Francisco) slowly slide past the view. Of course, “slowly” is just perspective; the ISS orbits at eight kilometers per second—18,000 miles per hour! But it’s also several hundred kilometers up, and distance does tend to change frame of reference.
And it’s not hard to see that video like this puts to rest the silly urban legend that the Great Wall of China is the only human-made structure visible from space. Cities, farm lands, dams, and even bridges are easily spotted, even without the zoom lens. Even better: The Great Wall is actually pretty hard to spot from orbit! It’s not actually that wide, and doesn’t have a lot of contrast with the surrounding land, making it difficult to see.
Don’t believe everything you hear. Or see. Or anything, actually: Always look for evidence. What you find might disappoint you at first, but it’s always good to learn something new. And you might stumble on something really cool … like photos taken by space-traveling humans as they fall endlessly around a blue-green world.