====== Reducing light pollution ====== There are tradeoffs here so how you balance them will depend on your goals. Light pollution harms wildlife and humans and uses energy. At the same time, well-lit streets increase safety, both from other humans and hazards, and basically help facilitate a functional nightlife, which is often an aspect of a thriving city. * The basics: * Use streetlights with caps that point downward – a huge ammount of light polution is reduced just by this step * Use redder lights – red light is less bright and better for wildlife, but still gives the same benefits (illusory or otherwise) for safety. It also doesn’t interfere with the circadian rhythm. Amber lights are better than white/blue. * A way to improve the feeling of safety is to light the faces of people, so you need lights at least taller than humans if you want them pointing downwards. Uniformity of lighting is also a big part, so multiple small lamps tend to be better than one big one. * Lights that switch off during especially low-traffic times * Consider if all areas of the city need light at the same times, or if some quiet neighborhoods can switch off earlier. * Prioritize lighting certain high-traffic areas, particularly in places with a lot of pedestrians, who might not all have their own lights or may be too inebriated to use them. These might include markets, streets with lots of bars/clubs/other nightlife, plazas, or anywhere people might socialize outdoors at night. * Cities with narrow, winding streets with buildings close will confine the light better than the opposite. * Curbs and other critical areas could be marked (not illuminated) by glow-in-the-dark paint or bioluminescent algae or plants.