Preserving Glacier’s Night Sky

Glacier National Park is known for its dramatic peaks and pristine alpine lakes, but once the sun sets, the park reveals an entirely different type of beauty: a clear dark sky. Glacier is one of the few places left in the United States where you can witness the thousands of visible stars in the Milky Way Galaxy. Currently, 80% of Americans cannot see the Milky Way from their backyards due to light pollution. 

The loss of our dark skies is an environmental concern and Glacier National Park is committed to reducing it. “We think about the dark sky as a natural resource, just like the wildlife or the water. If we lose the darkness, it fundamentally changes the ecosystem,” explains Debby Smith, Hudson Bay District Interpreter.

Seeing the Milky Way is a once in a lifetime opportunity for many visitors.

Thanks to the generosity of Glacier National Park Conservancy donors, Glacier has formed a long-term commitment to preserving dark skies and giving visitors the opportunity to experience the magic of stargazing. On August 12, 2021, Glacier, in close collaboration with Canada’s Waterton Lakes National Park, proudly earned its certification as an International Dark Sky Park from the International Dark Sky Association. To achieve this, the park had to rethink its lighting. New LED streetlights were installed to ensure that at least 67% of the lights within the park’s perimeter are “night sky-friendly.” This means that they only use outside lighting when necessary, lights are pointed downward, and they are restricted in their brightness.

“Preserving the night doesn’t necessarily mean turning out all the lights,” Debby explained. “But if we pay attention to small details it can have a significant positive impact on the environment, and ensure that the dark sky is something visitors can enjoy for generations to come.”

Logan Pass Star Parties are a popular way to learn about the night sky.

These improvements help sustain the natural cycle of day and night, a rhythm that life on Earth has relied on for billions of years. Illuminating the night with artificial light disrupts critical behaviors for many wildlife species:

• Migratory birds rely on cues from changes in daylight, season, and weather to know when to migrate. Light pollution can cause them to transition at the wrong time and miss ideal climate conditions, resulting in increased fatalities.
• Many insects are attracted to light, but interaction with light bulbs is often deadly. Declining insect populations negatively impact all species that rely on insects for food, such as bats and grizzly bears. Native plant growth is also reduced when pollinators are distracted or killed.
• Predators, like mountain lions, tend to avoid habitats with excessive unnatural lighting, which can lead to habitat fragmentation and changes in hunting behaviors.

Staying up to see the stars in Glacier is an unforgettable experience!

Because of the astronomy program, funded by donations to the Glacier Conservancy, ​interacting with the spectacular dark sky in Glacier National Park is a unique experience that can transform your perspective of the world. The astronomy program offers many educational opportunities throughout the summer. Visitors can join astronomers for a tour of the night sky through telescopes at the Apgar and St. Mary Visitor Centers. Star Parties, hosted at Logan Pass, feature park rangers, volunteer astronomers, indigenous storytellers, and a selection of cosmic viewing instruments.

“There’s nothing like seeing a visitor look through a telescope for the first time,” says Debby. “That connection, seeing Saturn’s rings or a distant galaxy, helps people understand why we work so hard to protect dark skies.”