Skylines at twilight are a photographer’s delight. But while cities bask in the glow, some are trying to remedy a side effect of growth: light pollution.
From space at night, Las Vegas is the brightest city on Earth. Pyongyang, North Korea, is the darkest.
The industrial age transformed cities, setting them aglow with light. In the late 1800s, as part of a revitalization of Paris, urban planner Georges-Eugène Haussmann had 20,000 gas lamps installed along its streets. He reportedly followed the motto “light before all else.” Since then, the City of Light moniker has stuck for Paris—and two dozen others have claimed it as well, such as turn-of-the-century Buffalo, New York, with its newly illuminated avenues.
Changing technologies have made cities ever brighter, as lights have gone from whale oil to gas to electric to LED. But those advances came with a consequence—light pollution. About 80% of us live in an area that’s bathed in artificial light at night. In North America and Western Europe, that number shoots up to 99%. Light pollution impacts both nature and humans, affecting our sleep cycles and even the hunting patterns of nocturnal animals.