Bright Leds Could Spell The End Of Dark Skies

Arthur T Knackerbracket has processed the following story:

Late one evening in June of 2016, John Barentine stood alone at Mather Point, an iconic and rarely empty overlook at Grand Canyon National Park. The moon slid away, leaving the darkness of a crisp, clear sky. The stars that make up our galaxy seemed to align overhead. The inky chasm of the ancient canyon spread out below, and he marveled at a feeling of being unmoored in time and space.

An astronomer who worked for the International Dark-Sky Association (IDA), Barentine had a special reason to revel in the scene. With his help, the park had recently been given provisional status as an International Dark Sky Park, a designation given to public land that exhibits exceptional" starry nights. Few publicly accessible places on Earth experience this kind of pristine darkness. Indeed, the view is quite different 200 miles away in Tucson. There, photons from the city's lights scatter in the sky, forming an obscuring dome of light called sky glow-a feature now common to major cities.

Scientists have known for years that such light pollution is growing and can harm both humans and wildlife. In people, increased exposure to light at night disrupts sleep cycles and has been linked to cancer and cardiovascular disease, according to a 2016 report by the American Medical Association. Meanwhile, the ecological impacts of light pollution span the globe. It can affect the reproduction patterns of male crickets, causing them to chirp during the daytime instead of at night, when they typically call mates. Baby sea turtles, which have evolved to evade predators by rushing to the ocean upon hatching, can be disoriented by lights near the shore. Owls lose their stealthy advantage over prey. Even trees can struggle, holding onto leaves longer and budding earlier than they should because the brightness of their surroundings gives them incorrect information on the time of year.

Astronomers, policymakers, and lighting professionals are all working to find ways to reduce light pollution. Many of them advocate installing light-emitting diodes, or LEDs, in outdoor fixtures such as city streetlights. Watt for watt, LED streetlights are now comparable in efficiency to traditional sodium vapor streetlights-and are in some cases more efficient. But the crucial difference is that they are better at directing light to a targeted area, which means less light and energy are needed overall to achieve the desired illumination.

Read more of this story at SoylentNews.