Lawmakers Act to Preserve Endangered Night Sky
By Kavan Peterson, Staff Writer
When was the last time you spotted the silky strands of the Milky Way spanning the night sky? For more than two-thirds of Americans, the answer is probably never.
Increasingly, the celestial nighttime view is being obscured by brightly lit shopping malls and the creeping glare of urban sprawl. In fact, 99 percent of U.S. residents live in areas tainted by excessive outdoor lighting known as light pollution, according to the National Aeronautics and Space Administration. The result is the Milky Way now is visible only in remote regions, astronomers say.
"That ability to see the Milky Way is truly a natural resource that should be protected, and to think that 80 to 90 percent of kids today are deprived of that is heartbreaking," said Leo Smith of the International Dark-Sky Association (IDA), a 10,000-member group based in Tucson, Ariz., that promotes darker nights.
For decades, astronomers have warned that the intrusion of artificial light is threatening to wipe out the starry sky. Now a growing number of city and state governments are taking up the fight to reclaim the night. For lawmakers, the issue is about energy efficiency and safety, as well as good stargazing.
Regulations aimed at reducing light pollution have been introduced in more than half the states in the past decade.
New Mexico requires lights out at 11 p.m. for all public and private parks and has banned high-powered mercury vapor bulbs for street lights under the state's Night Sky Protection Act, passed in 2000.
Arizona and Maine recently passed laws requiring all state-owned lighting systems to meet energy-efficiency and glare standards. Similar laws have been introduced in eight states this year: Connecticut, Hawaii, Illinois, Massachusetts, Minnesota, New York, Vermont and Washington.
More than 200 U.S. cities and nine states Colorado, Connecticut, New Hampshire, New Jersey, Pennsylvania, Rhode Island, Texas, Utah and Virginia have adopted more targeted laws regulating everything from the direction of billboard lighting to how late ballparks can stay lit up.
All these measures could help trim what IDA estimates is $2 billion wasted every year by Americans on lights that needlessly point upward and drown out the heavens.
One solution is as simple as making sure lights shine down, instead of up. This reduces the most common form of light pollution, called "skyglow," caused by unshielded and overly bright light fixtures, such as street lamps and bottom-lit billboards.
"When people hear we're trying to pass a bill to protect the night sky, a lot of them smirk at first," said Mike Lane, the legislative director for New York state Assemblyman Alexander Grannis (D), who introduced dark sky legislation this year. "But more and more they realize this is also about conserving energy and about safety."
The move to "take back the night" dates to 1958, when Flagstaff, Ariz., banned advertising searchlights in deference to the area's two prominent astronomical centers: the Lowell Observatory and the U.S. Naval Observatory.
From the Naval Observatory today, the nightglow from neighboring Flagstaff is less visible than the glare of Phoenix nearly 150 miles away, garnering Flagstaff the world's first International Dark Sky City designation last year from the IDA.
It wasn't until the 1990s that other officials got serious about light pollution.
The Milky Way became visible from downtown Tucson, Ariz., population 500,000, after city officials replaced 22,000 street lights with hooded light fixtures, said IDA director Dave Crawford. Forcing lights to shine down can recoup up to 50 percent of the illumination lost shining up, so the bulb's wattage can be cut in half to save electricity. The energy savings in Tucson covered the cost of installation in three years.
"What does it cost us to stop this problem? Nothing, we save money," said retired Air Force Lt. Col. Bob Gent, an IDA member and president of the Astronomical League, the world's largest association of amateur astronomers.
But cutting light pollution isn't always an easy sell. When it comes to safety, a lot of people think that brighter is better, Gent said.
Dark sky supporters say it is a myth that more light means less crime. In fact, over-lighting merely alleviates fear of crime, they say, possibly creating a false sense of security because glaring lights create deep shadows where criminals can lurk.
"It's counter intuitive, but people are finally catching on that focusing softer lights on the ground is better than blasting high-intensity lights in all directions, which can actually create a glare condition that can prevent police or security guards from seeing into dark corners," said Massachusetts Rep. Jim Marzilli (D), who introduced dark sky legislation in his state this month.
Glare from unshielded lights also contributes to traffic accidents, the American Automobile Association reports. The culprits often are overly bright retail signs and high-wattage floodlights along highways.
"People don't understand that type of lighting actually impedes vision and interferes with your ability to drive at night," said Gail Clyma, a light pollution activist in New York City who lobbied for dark sky legislation that passed the state legislature in 2001 but was vetoed by Gov. George Pataki (R).
The proposed law, which was reintroduced by Assemblyman Grannis this month, was opposed by the New York Department of Transportation and the energy industry. They objected to a provision that would allow people to sue over "light trespass" the unwanted light that crosses property lines, such as a neighbor's security floodlight or a neon gas station marquee.
"In a security sensitive environment, you really have to be careful that critical things are lit up to ensure safety and security," said Stephen Hanse, New York Energy Association vice president of regulatory and environmental affairs.
Light pollution also has an environmental impact on plants and wildlife, especially migratory birds and sea turtles, biologists say. The U.S. Environmental Protection Agency has no congressional mandate to monitor light pollution, but the agency has supported efforts in Florida to reduce beach light pollution to protect endangered sea turtles, which nest in the sand.
"It's just a matter of time before there are enough states that have adopted regulations like this that, at the national level, they'll realize they have to adopt this so all states have some uniformity," said Smith of the IDA, who helped devise dark sky legislation introduced in his home state of Connecticut this week.