Disappearing darkness

• The greater Phoenix area casts a nighttime arc of light over most of Arizona%2C extending more than 200 miles in each direction.
• Scientists estimate that in about 10 years%2C America will have only three dark patches of land where people will be able to clearly see the Milky Way.

When she's trying to explain the idea of light pollution, Laura Williams often shows people a picture taken from the South Rim during a blackout at Grand Canyon National Park.

It's mostly black, with some stars in the sky and a few car headlights, but then, there's this orange glow creeping from the south.

It's not coming from Sedona or Flagstaff, but from the Valley.

The Greater Phoenix area casts a nighttime arc of light over most of Arizona, extending more than 200 miles in each direction.

"People have a hard time believing it," said Williams, Grand Canyon National Park's night-skies inventory coordinator. "They don't realize how bright Phoenix is or how far light travels."

Williams is creating a system to identify unnecessary fixtures and too-bright bulbs so they can be replaced.

The idea is that increased darkness will mean Canyon visitors can better see the celestial bodies that make up our universe, and have an easier time considering their places in it.

But light from Phoenix car lots, Glendale billboards and Mesa strip malls floods the skies to the north, well past Flagstaff's Lowell Observatory, and well past Kitt Peak Observatory on the Tohono O'odham Reservation southwest of Tucson.

The glow washes out the skies from California's Joshua Tree National Park to the western edge of the Chihuahuan Desert in New Mexico.

For those living in cities, it can be hard to fathom why the word galaxy comes from the Greek for "milk."

It can be hard to appreciate that even above the white-glowing intersection at Central Avenue and Camelback Road in Phoenix — the Valley's midpoint — the Milky Way is above, shining brightly enough to cast shadows on Earth.

It can be hard to imagine that in truly dark spaces, people would run out of wishes before they'd run out of shooting stars.

Light pollution doesn't just bleach the night sky. It squanders electricity, does little to curb crime, disrupts life for animals including sea turtles, bats and migratory birds, and has been linked to everything from insomnia to breast cancer in humans.

"The whole issue isn't about not having light. It's how do we use light more responsibly and thoughtfully," said Paul Bogard, author of 2013's "The End of Night."

"The night is beautiful, amazing and filled with wonder," Bogard said. "What's the value of ... standing under the galaxy and wondering who you are and what your life is about? Losing it has an enormous cost to our souls and spirits."

Scientists estimate that in about 10 years, America will have only three dark patches of land where people will be able to clearly see the Milky Way and where they'll be able to do high-quality astronomy and nocturnal wilderness research.

Those areas are southeastern Oregon and western Idaho; northeastern Nevada and western Utah; and northern Arizona and southeastern Utah — the better part of the Colorado Plateau.

The light-sprawls of the greater Las Vegas and Phoenix areas imperil dark skies in both the Colorado Plateau and northeastern Nevada and western Utah. The Oregon-Idaho patch is not near large cities.

"Phoenix is in a unique position because it's such a large metro area so close to so many dark places," said Nathan Ament, coordinator of the Colorado Plateau Dark Sky Cooperative for the National Park Service.

"Your light affects people's experience in national parks and nocturnal wildlife environments," Ament said. "You can't just say, 'It's my backyard and I'll do what I want.' It's a shared resource."

The fact that two big cities can make a darkness difference is an anomaly. In the planet's brightest places, Europe, Japan, South Korea and the U.S.east of the Mississippi, light pollution looks like a mostly unbroken glow. It wouldn't matter if Paris forfeited its title as the City of Light, if Milan, Madrid and Oslo didn't tone it down, too.

Williams, Ament and others within the National Park Service are part of a 15-year-old movement, born in Western national parks, to inspire individuals to protect the skyskape.

During ranger talks, team members recommend putting landscape and architectural up-lighting on timers, putting security lights on motion sensors and making sure lights shine downward and only where needed. They talk about saving energy and money, and how easy it is to find the right bulbs and fixtures at, say, Home Depot.

Ament said rangers prefer to educate visitors about smart lighting, rather than lobbying municipalities to rewrite lighting codes.

"In the West, it seems to work a lot better for people to make decisions for themselves than if city or state or federal government tells them to," he said.

Astronomy at stake

Beyond conservation, there's the economic argument.

Arizona is home to three of the five largest telescopes in the continental U.S. And the bulk of America's telescopes are concentrated in the West. Many of them sit in Southern California and on or at the edges of the Colorado Plateau: around Flagstaff, Tucson and western New Mexico.

Astronomy, space and planetary-science fields bring Arizona $252.8 million annually. They attract about 200,800 visitors and employ about 3,300 directly and indirectly, according to a 2008 study by the University of Arizona, the most recent available.

The future of this industry depends on darkness.

That's why Tucson, among other Arizona cities, implemented dark-skies-friendly lighting codes decades ago. Tucson hasn't gotten brighter in 30 years even though the population has increased 59 percent since 1980, said Katy Garmany, an associate scientist at the National Optical Astronomy Observatory outside Tucson, which just completed a study of Tucson's skyglow.

But scientists at the National Observatory on Kitt Peak estimate that if the Valley continues to brighten, they've got about 10 years left, said Garmany.

Then astronomers will have to travel to Hawaii or Chile to do certain research, such as trying to spot planets outside our solar system.

"It keeps getting brighter and brighter," Garmany said. "It's just really hard to do the cutting-edge stuff, and you have to go ... where it's darker. (Scientists) have ways of eliminating extra scattered light in the sky, but there's only so much they can do."

Creating dark skies

John C. Barentine is the dark-skies places program manager for the Tucson-based International Dark-Sky Association. He leads the team that designates places as having the kind of low but adequate lighting sufficient to preserve the nightscape.

Flagstaff was the first International Dark Skies Community in 2001. Barentine's team has designated only seven other communities and 25 parks and reserves globally. Sedona was added to the list earlier this year.

Barentine grew up in Phoenix and remembers the first time he saw the Milky Way.

"To say it was shocking would be an understatement," he said. "I was 10 or 11 years old. We were up in Flagstaff to play in the snow. I remember going outside … and I was floored. I was absolutely floored."

Now, he spends his days helping communities create lighting codes so kids don't have to ride in the car for 90 minutes to be filled with awe at the night sky.

He goes to town halls and city planning meetings to talk about how putting lights on timers and sensors, adding shields to the tops of lights and choosing amber bulbs or lower wattages can all reduce skyglow without impacting ground visibility.

Barentine sighs when he talks about Phoenix, but said the city's lighting codes "aren't bad."

The city has site codes, which were last updated 11 years ago, and street-lighting codes, which were last updated two years ago. The site codes don't apply to lights older than 1985, although there aren't many still in use. But if a building is new, the lights must conform to updated codes, which call for the kinds of lights Barentine recommends.

But issues remain. Asphalt is more reflective than dirt or grass, and lighting codes don't address ground glare. Horizontal lighting, a main cause of skyglow, is common here: Think of strip-mall signs lit from within. Common white and blue lights, even LEDs, glare more than other colors.

And enforcement is an issue.

"We don't have the right equipment, time or staffing to do that," said Tim Boling, the deputy director of neighborhood services for Phoenix.

Last year, Boling's staff closed 70,000 complaint cases, and he estimates only three or four were related to lighting violations.

In Flagstaff, which adopted dark-skies codes in 1989, all outdoor lighting is low and amber-colored, even at the hospital and jail. But people can see easily because nothing is significantly brighter than anything else. And safety isn't an issue. Research across several disciplines has shown that more light doesn't necessarily make buildings or streets safer.

Here's why: The human eye adjusts to the brightest thing in the landscape. This is why in starlight, if a woman waits 15 to 45 minutes, she can see her way along a path, or find dropped change on the ground.

But introduce a set of headlights, an iPhone screen or a luminous watch face, and all of her dark-adaption gets blown out. It's why in dark rooms, humans are blinded by camera flashes.

It's why at El Tovar Lodge on the South Rim, visitors on the light-filled front steps can't see elk 20 feet away.

It's why a gas-station canopy makes everything around it seem dim, causing neighboring businesses to add lights proportionally.

In some cases, diminishing nighttime lighting can improve visibility. Reflectors, like on the edges of highway lanes, or limited guide lights, like on runways, work better than adding floodlights because the key to visibility is contrast, not overall brightness.

To preserve the work done at Lowell, an acre can have only 50,000 lumens in parts of Flagstaff. (A lumen is a measurement of how much light a bulb puts out. A 40-watt incandescent bulb puts out 450 lumens; a 100-watt one puts out 1,600 lumens.)

In contrast, in parts of Maricopa County, a single sign can give off 40,000 lumens. Barentine's association recommends a sign not exceed 3,000 lumens. In Phoenix, there are no lumen limits at all. In the Valley, the brightest things are gas stations, billboards and car lots, all using wattage to attract attention, Barentine said.

Thirty-two municipalities make up the Valley, and since Phoenix is constricted from substantial growth by the surrounding municipalities, it will take all of them working together to limit skyglow, said Alan Stephenson, the director of Phoenix's planning and development department.

It's not on people's short lists, though.

"When we talk to downtown residents, they're more concerned about street lights being broken, or safety, when it comes to light," said Stephenson.

People aren't against dark-skies-friendly lighting codes, though. They just don't think about light pollution, said Christian B. Luginbuhl, an astronomer at the United States Naval Observatory in Flagstaff.

"They're focused on their day-to-day jobs and whether the traffic is bad or whether they can buy the things they need for their families," said Luginbuhl. "They don't notice that the stars are gone. And if they do, they think, 'Well, that's what it's like to live in a city.'

"But it doesn't have to be that way, and they can demand more."

Special interests derail efforts

Once, there was a movement to demand more.

In 2009, the Maricopa Association of Governments formed the Dark Skies Stakeholders Group to study ways to protect the state's astronomy industry from Maricopa County's glow.

Typically, the association coordinates the policies that make it easy to live in cities that border each other, setting standards and best practices for things like air quality and solid-waste management.

The group was composed of 96 people, scientists, city engineers, transportation-safety experts, town planners and representatives from banking, retail and signage organizations.

They worked from January 2009 to April 2011, examining light-use studies from around the world, interviewing experts about best practices and weighing concerns from stakeholders and the public in meetings.

They drafted an 87-page public document that called for limiting lighting throughout Maricopa County to 150,000 lumens per acre, or three times most of Flagstaff's limit.

When the plan was presented for approval to an internal MAG board, members who had not previously attended meetings raised concerns about safety, liability and diminished commerce.

Those members included the International Council of Shopping Centers, the Arizona Food Marketing Alliance, Arizona Retailers Association, Arizona Sign Association and International Sign Association, and the Arizona Bankers Association.

According to the meeting's minutes, only one association representative presented a case study. None of the others produced supporting data.

"They withheld their participation until the end, and then they tried to create a train wreck," said group member Luginbuhl. "They said it would cost people money and hinder commerce, and it derailed the entire thing."

Luginbuhl had seen this before. In the late 1980s, he'd been instrumental in designing Flagstaff's lighting codes to protect the views from Lowell Observatory. He watched the same groups bring up the same issues.

But at a crucial public meeting in 1989, the deputy county attorney spoke up, saying liability was not going to be a problem. The planning and zoning commission sided with the scientists who said visibility would not be a problem, commerce would continue, and people would stay safe. Flagstaff passed stricter lighting codes.

Since then, neither Flagstaff nor any of the other International Dark Skies Communities has turned into a commerce-free, crime-filled Gotham. The retail centers, banks and gas stations have remained easy for people to find and patronize, even at night.

The Maricopa Association of Governments has not addressed the issue since.

Celebrating dark skies

"By day, the Canyon makes you feel small," said park ranger Marker Marshall. "By night, the sky does too."

It was late June, a week without a moon, and Marshall was hosting a ranger talk called "Starry Starry Night: A Tour of the Universe As Seen Over the Grand Canyon" as part of the 24th Annual Grand Canyon Star Party.

The auditorium was at capacity, with 233 people ready to learn how to use a sky map and discern a planet from a star. Kids clutched workbooks, eager to earn the Junior Ranger Night Explorer patch, deep blue and featuring Ursa Major.

Marshall wore tiny gold earrings shaped like Saturn. She said things like "Deneb is 54,000 times as luminous as our sun, putting out more energy in 10 minutes than our sun does all year. The light that we can see now left Deneb in 403 A.D., around the time of the fall of the Roman Empire."

Marshall grew up in New York City and remembers the night sky as orange. But one night when she was 7 and visiting her grandparents in rural Canada, they watched the Apollo 11 moon landing on TV.

"And it was amazing. But then we went outside and went out to look at the moon, and it was amazing all over again," Marshall said.

Marshall earned a biology degree at Smith College and soon got a ranger job at Organ Pipe Cactus National Monument in southern Arizona, where she memorized a new constellation each night.

There, at the start of her dark-skies programs, she'd just turn off the lights and the sudden appearance of so many stars would make people clap and exclaim.

Later, she spent three years taking 96 astronomy classes as part of the Great Courses lifelong-learning program. The Whirlpool Galaxy is her favorite. "It's so pretty."

Just outside the auditorium, professional and amateur astronomers had set up 51 telescopes, each trained on a different celestial body.

More than 100 astronomy volunteers trek to the Canyon each year for the star party, mostly from Tucson. They bring telescopes and years of formal and informal expertise.

Mostly retirees, they coach people on how to peer through the lenses at Mars or Vega, and how to track their eyes along a green laser up to the collection of stars that looked to Ptolemy like a swan or a queen on her throne.

Just after 9 p.m., more than 1,000 people in hoodies and jeans wandered among the telescopes. The lot filled with shouts of "Wow!" and "Mom, come see this!" And, more breathless, "I had no idea."

Erich and Karen Shofstall drove from Livermore, Calif., with their two daughters to look at the stars. Kate, 10, said the drive took "forever."

"We can explore and learn and see some cool stars and some of the planets," said Erich. "It's really educational. I think the kids like it."

"We've seen Mars and Jupiter and Saturn," Kate said.

"How 'bout those nebulas?" asked Erich.

"Yeah, we've seen those, too," Kate said, taking the universe in stride.

"We get so many people who realize they've seen their first planet, first shooting star," Marshall said. "It's so special.

"People need the sense of beauty and perspective and awe that we get from our exposure to the universe in a dark night sky. It's part of every culture, part of being human — to contemplate what's above us."

Across the parking lot, a retired plastic surgeon from Boston led a constellation tour, which is to say, he stood in one place and pointed up with a laser.

"All that stuff you see is not clouds," he said. "It's perfectly clear tonight. It's the Milky Way."

A collective gasp rose from his small audience.

ON THE BEAT

Megan Finnerty is a reporter on the Page One team. She is the founder and host of the Arizona Storytellers Project. She loves the Grand Canyon. She has been with The Arizona Republic since 2002.

How to reach her

megan.finnerty@arizonarepublic.com

Phone: 602-444-8770

Twitter: @MeganMFinnerty