Light pollution is getting worse. Colorado state parks are working to protect the night skies.
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GOLDEN, Colo. — The first time Maggie Martin pointed her camera towards the night sky, she captured a meteor.
It was 2011, and Martin — a special education teacher at the time — had decided to take an astrophotography class at Rocky Mountain National Park.
“My focus was off, but I had this blurry picture that I was infatuated with. It blew my mind,” said Martin.
For the 25 seconds she exposed her camera, Martin felt fully present.
“I was a school teacher doing 6,000 things a minute. It was something that slowed me down. It taught me to meditate. It got me curious and creative,” said Martin, who left teaching during the COVID-19 pandemic and now leads astrophotography workshops and client photoshoots in the mountains west of Denver.
Martin is part of a growing contingent of astronomers and photographers who seek out dark sky sites that offer the best conditions for stargazing. Last year, Condé Nast called astro-tourism one of the year’s biggest travel trends.
At the same time, scientists estimate that globally, light pollution is increasing by 10 percent every year. That means, “if there are 250 visible stars in the sky when someone is born, by the time they're 18 they'll see only 100, and over that same period the sky will have increased in brightness by more than a factor of four,” wrote Phil Plait in a Scientific American article describing the study.
In an effort to protect night skies and promote stargazing, 12 Colorado state parks are partnering with DarkSky Colorado, a chapter of the DarkSky International, to reduce light pollution and become dark sky certified destinations.
DarkSky Colorado is a nonprofit that works to restore “the nighttime environment” and protect “communities and wildlife from light pollution.” The organization started in 2019.
“Reducing unnecessary light pollution saves energy, enhances stargazing tourism, and protects Colorado's breathtaking night skies for everyone,” said Colorado’s Democratic Governor Jared Polis in January.
The announcement came three years after state representatives passed House Bill 22-1382 to allocate funding for technical assistance to Colorado applicants working to become dark sky sites.
At Golden Gate Canyon State Park — 30 miles west of Denver — Bronwyn Phillips waited for the sun to dip below the horizon on Feb. 27. Phillips, an administrative assistant at the park, conducted her first monitoring trip at the end of February. These data will provide a baseline for how dark the night sky is at Golden Gate Canyon.
The first location Phillips recorded was the Nott Creek Trailhead. Phillips used a handheld sensor called a sky quality meter, which measures how bright the sky is in magnitudes per square arcsecond. The higher the number, the darker the sky.
Phillips visits seven locations throughout the park with each monitoring visit.
The new moon provided the right conditions for Phillips to measure. Too much cloud cover or lingering snow on the ground can also interfere with the accuracy of her measurements.
At the Nott Creek trailhead, Phillips held the sensor directly above her head and took six readings. The average reading was 20.1 magnitudes.
“For dark sky parks, you want that measure to be 21.2 or higher,” said Phillips.
From the trailhead, a faint glow lingered behind the mountains to the east. The light pollution from Denver makes it unlikely Golden Gate Canyon will meet the same dark sky thresholds as places, like Jackson Lake State Park, which is located on Colorado’s eastern plains.
Colorado is home to 12 certified dark sky parks and six communities. Black Canyon of the Gunnison National Park and the towns of Westcliffe and Silver Cliff were the first places in the state to become certified in 2015.
Instead, Phillips said Golden Gate Canyon will look to become an “urban dark sky place.”
This means that although the park won’t meet the highest thresholds set by DarkSky Colorado, the park will still provide opportunities for visitors to learn about dark skies and view the stars. Park officials will also implement plans to reduce light pollution at the park.
“We have to protect what we have now,” said Phillips.
Aaron Watson is one of the mentors with DarkSky Colorado who will help state parks to become certified, a process that could take up to three years.
Watson said light emitting diodes, or LEDs, are one of the culprits leading to exponential increases in light pollution globally.
That light pollution can confuse migrating birds, harm pollinating insects and lead to increases in metabolic disease, obesity and worse mental health in people.
Places like Golden Gate Canyon are extremely important because they offer opportunities for people to come and learn about why it’s important to protect the night sky, said Watson.
According to Phillips, more than 1.7 million people visited Golden Gate Canyon State Park last year. Visitation spikes when the park's aspens change color in the fall and before Christmas, when people come to the park to cut down trees.
Unlike most activities, however, astro-tourism encourages people to visit during off-peak hours.
“You can go out to these places that maybe are crowded during the peak of the day, and you get to experience it in this whole new way,” said Martin.
The first step state parks must take to become certified is community outreach. Parks must host events like star viewing parties or guided nighttime hikes for visitors to learn about dark skies.
Next, workers must measure the quality of the night sky in their park. The third step is to conduct an inventory of publicly managed lights.
“We take a picture of each light, write down the specifications like shielding, lumens, and color temperature,” said Watson.
At Golden Gate Canyon, lights are clustered near the visitor center, maintenance shop and campgrounds.
Finally, participants in the program must devise a lighting management plan to govern lighting decisions going forward. For towns and cities seeking dark sky status, this often takes the form of a legally binding lighting ordinance or land use code.
Watson said the three biggest benefits of pursuing dark sky certification are an increase in quality of life, economic development and energy savings.
He first became interested in the idea of dark skies when he moved to Paonia, Colorado. The town’s remoteness offered Watson crystal clear views of the sky.
Watson recognized the value of protecting Paonia’s darkness and joined an initiative to help Paonia become a certified dark sky community. The process took more than six years, but Watson thinks it will pay dividends for years to come.
“We used to be a really big coal mining town, and that industry has dried up,” said Watson.
He thinks that astro-tourism can help communities pivot toward tourism-based economies.
A 2024 economic analysis of Great Sand Dunes National Park — a gold tier international dark sky park (DarkSky International’s highest tier) — found, “that even slight increases in light pollution—to levels comparable with nearby Alamosa or Breckenridge—could result in annual tourism revenue losses between approximately $176,000 and $295,000, with broader regional GDP impacts due to reduced visitor spending.”
Despite the economic benefits dark sky tourism can create, Watson said that the most common concern people have is that reducing light could lead to new safety concerns or unnecessary red tape.
“We call ourselves dark skies, that doesn't necessarily mean dark ground,” said Watson.
Small changes, like using different bulbs, changing the angle of lights or using motion sensing lights can make a big impact, said Watson.
“The more black the sky becomes the more stars that are visible, and the more textures of the Milky Way that you’re able to pull out,” said Martin.
Although going to a dark sky area makes it easier to take pictures at night, Martin encourages people to experiment with astrophotography wherever they can.
During her classes, Martin uses DSLR or mirrorless cameras, but some smartphone cameras also provide the ability to manually adjust aperture, sensitivity and shutter speed to capture pictures at night. In addition to a camera with manual controls, a tripod is necessary to keep the camera stable during long exposures.
As far as weather, clear, cloudless nights are ideal. Wind is another factor to consider, since it can shake your tripod, said Martin.
“[The stars] are not something you can just drive to and go see. There's so much that's unknown,” said Phillips. “And I think a lot of people, when they look up, they remember how small they are. It's just kind of a nice humbling reminder.”
Type of story: News
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources.
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources.
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