Despite brilliant lights in urban areas surrounding Las Vegas and Reno, Nevada boasts some of the darkest night skies left in the nation.
Mapping and photography from satellites and spacecraft reveal that intense city lights dim views of night skies around the world. City dwellers see only the brightest stars and planets, losing views of the Milky Way, constellations and thousands of stars that used to be visible to the naked eye.
Light pollution troubles scientists because it is getting harder to study stars and planets from established observatories. Other worries arise over the loss of yet another connection to our environment, especially for people living in urban areas. Such concerns led to the growth of the Dark Skies Initiative and formation of activist organizations such as the International Dark-Sky Association.
Activists promote the use of lighting with less spillover, concentrated downward to target city areas where people and property need lighting for safety and security. They push for lighting ordinances banning uncapped street lights and indiscriminate use of high beam spotlights, searchlights and field lighting. Flagstaff, Ariz., home to an observatory and just 60 miles from the Grand Canyon, was the first community in the world to pass ordinances addressing light pollution, in 1958. When other communities follow suit, they successfully enhance their night-sky views, but many cities take no action at all.
Sadly, 70 percent of all Americans cannot experience the brilliance and beauty of the celestial night display. The problem will be explored July 5 when a new documentary, "The City Dark," premieres on public television. Light pollution concentrates in the eastern half of the United States, along the Pacific Coast and around large inland cities. Being less populated, the western half of the nation has far less intense light pollution, particularly in the intermountain states, except for urban centers. In Nevada, reflected light from Las Vegas is visible from north of Beatty and light from Reno as far south as Hawthorne.
Interest in restoring views of the night skies and educating people about what they are missing sparks growth in tourism to places with dark skies. Remote areas benefit from promotion of this kind of eco-tourism. In Nevada, former mining queen Tonopah plays up its mention as a dark-sky destination in national publications. The town outlines "star trails" for visitors to follow, paved routes in Central Nevada fanning out from Tonopah.
Recent celestial events involving the moon, a special eclipse and a once-in-a-lifetime view of Venus casting its shadow across the sun pique public interest in astronomical activities. Stargazing parties with knowledgeable rangers, amateur astronomers and telescopes are popular in many national and state parks and recreation areas in regions noted for their dark skies.
In Nevada, Great Basin National Park offers information on its website about dark skies, light pollution and astronomy-related activities. Investigate at nps.gov/grba. The nonprofit Great Basin National Park Foundation supports and promotes night-sky observation projects. Clear skies and high elevation make for good viewing at Great Basin. The park winds up its annual astronomy festival this weekend, and other events continue through the summer.
Weekly evening astronomy programs featuring a ranger talk followed by telescope use are scheduled on Tuesdays, Thursdays and Saturdays through Labor Day. Full-moon hikes promise nocturnal adventures on July 3, Aug. 2 and Aug. 31. These hikes are limited to the first 40 visitors who pick up a free ticket in the Lehman Caves visitor center on the day of the outing.
The Perseid meteor shower viewing on Aug. 13 promises sighting of at least 60 meteors an hour. Dark-sky events elsewhere in Nevada are planned at Fort Churchill and Cathedral Gorge state parks. At Fort Churchill, attend a star party from 8:30-10 p.m. Saturday in the cemetery parking lot, where telescopes will be set up. Join a ranger for a full-moon hike July 1 or Aug. 31. The Las Vegas Astronomical Society plans its fall star party at Cathedral Gorge State Park Sept. 14-16.
Margo Bartlett Pesek's column appears on Sundays.