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The Great Wall of China
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Image
Above
Great Wall of
China
Edsitement |
Construction on the Great Wall
of China started around 700 BC.
Contrary to popular beliefs, the
Great Wall is not visible from the moon. Nor does it run in
a single line.
Neil deGrasse Tyson explains in
his Space Chronicles:
From the window of the International Space
Station, which orbits at about 225 miles up,
you might find London, Los Angeles, New
York, or Paris, in the day time, not because
you can see them, but because you learned
where they are, in geography class.
At night, brightly lit mega cities present
as patches of glow. By day, contrary to
common wisdom, with the unaided eye you
probably won't see the pyramids at Giza. And
you certainly won't see the Great Wall of
China. Their obscurity is partly the result
of having been made from the soil and stone
of the surrounding landscape.
And although the Great Wall is thousands of
miles long, it's only about 20 feet wide;
much narrower than the U.S. interstate
highways you can barely see from a
transcontinental jet.
Now, that's the view from the space
station. But what's the distance between Earth and Moon?
NASA explains:
The moon is an average of 238,855 miles
(384,400 km) away. How far away is that?
That’s 30 Earths.
Back to the Great Wall.
Best described as a complex
building project, the Great Wall of China consists of many
walls. These walls were built throughout the centuries and
marked different borders at different times.
Here is the map:
Great Wall of China 700 BC
More History
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