With up to a million people predicted to come to Idaho to watch the solar eclipse on August 21, the sky is big business. While day turning to night is rare to see, the night sky is a spectacle unto itself.

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In town, you might see just a few stars, but in the wilderness – away from the glow of the city – the sky puts on a show each night. In Idaho’s Sawtooth National Recreation Area, one of the darkest places left in the lower 48 states, a campaign is underway to save the pristine sky.

The evening air is cooling off as the twilight fades to black and the moon slips behind the Sawtooth Mountains. At a campsite just off Highway 75 a little south of Stanley, City Councilman Steve Botti is standing by a crackling campfire with a glass of wine in his hand. He’s waiting for it to be truly dark.

Once the sky finally transitions from deep purple to a rich black with a host of stars starting to shimmer, Botti suggests we walk away from the campfire “to let our eyes really adjust because even that bit of light really makes a lot of difference,” he says.

In the high mountain valley with the Sawtooth range to the west and the White Cloud Mountains to the east, we’re miles from the nearest town – let alone city – that could be sending light up into the air.

We walk away from the fire and go about 30 yards. Where we’re standing, Botti’s car is blocking most of the light. He takes out what looks like a pager and holds it up to the heavens. It beeps several times, and a red number appears on the digital display: 21.54.

“So, 22 is considered as dark as the sky can get – no light pollution, no sky glow – and I’ve gotten readings of 22 here in this valley,” says Botti. The little pager he’s holding is called a sky quality meter; it measures the darkness of the sky.

Botti is leading the effort to get this rural and rugged area designated the first International Dark Sky Reserve in the U.S. Eleven similarly-dark places around the world have gotten the designation, but getting to a reserve in central Idaho is a lot easier than going to see a couple of the other reserves in Namibia or New Zealand.

In the crisp air, our backs to the fire and our necks craned upward, the night sky is luminous. Tens of thousands of little dots shimmer as shooting stars streak by every few minutes. And arching over us, the Milky Way itself is visible.

In the darkness, Botti points to the shadowy haze of the galaxy bending over us.

“Along the arc of the Milky Way, there are dark bands within the stars which is the galactic dust, and you can see those because the stars are so bright,” he says.

Over the last two years, Botti has been routinely measuring the darkness of the sky. He’s also worked to curb light pollution in Stanley to meet strict standards and collaborated with the neighboring communities of Sun Valley, Ketchum and Hailey to land the reserve status.

According to John Barentine, the program manager for the Arizona-based International Dark Skies Association, of the five designations the organization has, reserve is the most difficult to land.

Barentine says the people in this remote corner of Idaho reached out to him.

“They told me that they view the nighttime darkness and, you know, the ability to see the Milky Way, as something that is definitive of their part of the state and their part of the country.”

For years now, Barentine and others at the association have been collecting sky quality readings from the Sawtooth region to gauge the suitability of the proposed reserve.

Barentine describes the certification system as one of trust by verify: “We trust the measurements that the applicants make from on the ground, and we verify it by looking at data from Earth-orbiting satellites that are looking down on the Earth at night.”

Those satellites corroborate the deep darkness Botti routinely measures in the Sawtooths. While the Dark Skies Association’s mission is preserving the experience of seeing an unpolluted night sky, Barentine says gazing at myriad stars is something tourists are increasingly drawn to.

“A daytime visit to a place like the national recreation area might not have the same degree of economic impact, so dark skies means at least an overnight stay,” he explains.

Down the road from Stanley and over the Galena Summit is Ketchum. After this summer’s total solar eclipse, the Wood River Valley city will be no stranger to sky-watching tourists. As she sits on the patio of the restaurant she runs with her husband, Ketchum Mayor Nina Jonas says she’s bracing for record levels of visitors.

“They’re telling us to anticipate three to four times our maximum tourism load for a single event,” she says. “That’s very evidential of the fact that people do come for the love of the sky.”

She’s nervous but excited for the huge influx of visitors coming to witness the celestial spectacle. Jonas says Ketchum was an early adopter of policies that keep the sky in mind and curb light pollution; it passed its first Dark Skies ordinance in 1999.

As proposed, the more than 900,000-acre central Idaho dark sky reserve would include Ketchum, Hailey and Sun Valley on the periphery with tiny Stanley right on the edge of the core where the sky is darkest.

In the Sawtooth Valley, back at the campsite, the moon has totally set, the air is chilly, and the heavens have gotten even clearer. It’s a little after midnight when Steve Botti pulls out his sky quality meter one final time before heading a few miles up the road to his home back in Stanley.

As he holds it up, he says, “A reading of 21.75 or higher is considered by the Dark Sky Association to be exceptionally dark.”

He pushes the button. Beep. Beep. Beep.

“21.76,” he reads on the digital display with satisfaction.

A couple years into the application process which usually takes around three years from start finish, Botti and his partners in the neighboring towns will soon submit their final paperwork seeking recognitions for their skies. If it’s accepted, the country’s first International Dark Sky Reserve could be in the Idaho backcountry as soon as next year.

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