For someone standing on the North Rim of the Grand Canyon on a moonless night, the brightest feature of the sky is not the Milky Way but the glow of Las Vegas, a hundred and seventy-five miles away. To see skies truly comparable to those which Galileo knew, you would have to travel to such places as the Australian outback and the mountains of Peru. And civilization’s assault on the stars has consequences far beyond its impact on astronomers. Excessive, poorly designed outdoor lighting wastes electricity, imperils human health and safety, disturbs natural habitats, and, increasingly, deprives many of us of a direct relationship with the nighttime sky, which throughout human history has been a powerful source of reflection, inspiration, discovery, and plain old jaw-dropping wonder.
— "The Dark Side" by David Owen in the New Yorker