Jodi Peterson, HIGH COUNTRY NEWS
Research paper: The new world atlas of artificial night sky brightness
International Dark Sky Association
The next best chance for Westerners to see shooting stars is coming soon, between April 16 and 25, when the Lyrids meteor shower, one of the oldest known, will streak across the sky after midnight. In May the Eta Aquariids arrive, followed by the Delta Aquariids in July, and then the most spectacular of the year — the Perseids, fast, bright meteors, up to 200 an hour during Aug. 12 to 13, and the Geminids, kid-friendly because they show up soon after dark, from Dec. 7 to 17.
But none of these, of course, will be visible without sufficiently dark skies.
For most of us, that will mean traveling far outside city limits to a place away from streetlights and other artificial illumination. But in some less-populated places, like High Country News’s western Colorado hometown of Paonia, the Milky Way’s glow can be seen on any clear night. That’s because Paonia is a tiny town in the high desert, with just 1,500 residents surrounded by public lands, orchards and farms.Map of North America’s artificial sky brightness.
Natural darkness is important for a lot more than just stargazing, though. It’s also vital to scientific astronomy studies, migrating birds and night-flying insects. And exposure to blue-rich light at night, from computer screens and outdoor LED lights, disrupts people’s sleep cycles and may even contribute to cancer. At its January meeting, the American Astronomical Society passed a resolution “affirming that access to a dark night sky is a universal human right, making quality outdoor lighting a worldwide imperative.”
Some bigger Western cities have put a lot of effort into curbing and redesigning their light usage so that they can have dark skies, too. Flagstaff, Arizona, passed the nation’s first dark-sky ordinance in 1958, to preserve starry conditions necessary for research at the Lowell Observatory.
That nearly six-decade-old effort seems to have paid off. Today, nighttime images captured by the National Park Service show that Flagstaff emits far less artificial light than other cities of its size. The 65,000-resident city uses sodium street lights. In contrast to LED lights, which save energy but produce bright blue and white light that washes out stars and planets, sodium lights emit a warm red-yellow light that doesn’t contribute much to overall sky glow. Flagstaff also banned commercial searchlights and shielded outdoor lights around schools and shopping centers. In 2001, it became the world’s first international dark-sky city, as designated by the nonprofit International Dark-Sky Association.
Read more at: Western cities try to cut light pollution — High Country News
