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Geography

The Geography of Night-Time Light Pollution and Urban Sprawl

Quick fact

Satellite images of night lights show that urban areas cover only about 1% of the Earth's land surface, yet they emit most of the artificial light, with some regions so bright that they are visible from space as continuous urban corridors stretching for hundreds of kilometers.

Why this is interesting

Have you ever seen a map of the Earth at night—a glittering web of lights? That map is not just beautiful; it reveals the hidden geography of where we live and how we've reshaped the planet.