Environment Pollution We're Losing the Nighttime Sky By Melissa Breyer Editorial Director Hunter College F.I.T., State University of New York Cornell University Melissa Breyer is Treehugger’s editorial director. She is a sustainability expert and author whose work has been published by the New York Times and National Geographic, among others. our editorial process Melissa Breyer Updated October 11, 2018 ©. National Park Service Share Twitter Pinterest Email Environment Planet Earth Climate Crisis Pollution Recycling & Waste Natural Disasters Transportation But fortunately, unlike many other natural resources, darkness is renewable. A study was recently published which found that visitors to Maine's Acadia National Park value the nighttime sky. Nearly 90 percent of those asked for the study agreed or strongly agreed with the statements, "Viewing the night sky is important to me" and "The National Park Service should work to protect the ability of visitors to see the night sky." Well, of course. The only surprising thing there is that the number wasn’t 100 percent. But beyond the obvious – that people like to see stars at night, go figure – the researchers arrived at some surprising findings. According to the study, led by Robert Manning of the University of Vermont, 99 percent of the world's skies are victim to light pollution. And sadly, two-thirds of Americans can't see the Milky Way from their homes. Residents of major metropolitan areas are lucky to see even just a smattering of stars once the night washes over the heavens. It’s kind of crazy to think that even in National Parks, dark skies are threatened. Most light that hampers the nighttime views in National Parks comes from development, the study notes. Light from cities or towns can travel to parks and dim the view from as far away as 250 miles. "It's a typical story," Manning says. "We begin to value things as they disappear." Fortunately, he notes, there are things we can do to restore darkness in the parks. The study created data to help Acadia develop strategies to deal with the problem; those plans can be used by other parks as well. Tackling light pollution requires work from both inside and outside the park, Manning says. "Inside the park, you want to eliminate as much unnecessary light as possible," he says. "Outside, the goal is to minimize light trespass. That's more challenging, but possible." Manning suggests that for inside the park, visitors should use as little light – flashlights and headlights, for example – as possible. Since astronomical tourism is a growing market segment, it’s hopeful that nearby towns and cities may recognize the financial benefits of pitching in to help solve the problem. One action that would have a big impact is that older light sources disperse illumination horizontally rather than directionally. By converting to LEDs and/or other directional lighting, parks and neighboring developments can help a lot to reduce light pollution, says the study. Acadia has been successful in restoring darkness to their skies by working with the next-door neighbor city of Bar Harbor to implement a progressive lighting ordinance. Another example of success is Chaco Culture National Historical Park in New Mexico, which partnered with stakeholder groups, says the study, to successfully encourage the state legislature to pass the New Mexico Night Sky Protection Act. Until the value of seeing stars is recognized and worked towards in a much more mainstream way, however, there are still places to gaze at the heavens ... and actually see them. Read 19 dark-sky parks where the heavens steal the show for more.