Dark skies are disappearing across the United States.

Today, more than 80 percent of Americans can’t see the Milky Way from their home cities. But deep in rural Idaho, the skies are alive.

The International Dark-Sky Association has named nearly a million acres in central Idaho a Dark Sky Reserve, a designation that means counties and towns in the area pledge to take measures to keep the dark, well, dark.

To get the honor, local homes and businesses had to abide by local ordinances limiting light pollution. This includes changing to outdoor light bulbs that emit soft yellows and aiming them downwards to get a better view of the night sky. VICE News went to Ketchum, ID to learn about how the reserve came to be and why it’s so important.

“Blue light and shorter wavelengths of light are important to adult behavior and human health, and animal health,” said Brett Seymoure, a behavioral ecologist at Colorado State University. “This evolved so we know when it’s night and when it’s day. So you have a blue light, it’s telling you that it’s day even though it’s night. 

This segment originally aired December 19, 2017, on VICE News Tonight on HBO.