Lightscape / Night Sky
NPS Photo by Mike Bromley
Even for those of us with limited knowledge of astronomy, the night sky is a part of the park experience. It gives us a place and time to sit back and peer into the endless unknown.
The darkness is part of nature's clock. The changes in light and dark trigger hormonal changes in wildlife. Elk notice the early fading of daylight into dark in the autumn. This triggers their mating season. The challenging bugle of the bull elk echoing through the hills and valleys introduces us to one of the amazing sounds of the wild.
However, no matter what the season, night is an active time in the park. Owls soar silently through the sky. Bats hunt insects, eating them by the thousands. Coyotes howl in harmony and bison bellow during their mid-summer mating season.
It is the mission of the National Park Service to protect the animals and the culture of an area but this is only part of the mission. The environment in which these wonderful things are found must also be protected. That means that the night sky over the parks must be protected.
Protecting the dark is a challenge. In the park, we have eliminated lights that are not needed and shielded others whenever possible. Still, as the cities around us grow, so does the amount of light pollution they send into the sky. An awareness of light pollution is important and is growing.
The Environmental Protection Agency has a program, Energy Star, which helps industry use appropriate lighting. Other non-profit organizations like the International Dark-Sky Association and the National Parks and Conservation Asssociation are leading an effort to help raise awareness and eliminate lights that block the night sky. For more information see their website.
Experiencing the prairie while surrounded by the inky blackness of the night interrupted only by the glow of the northern lights, a distant lightning storm, or the quick flash of a shooting star, is a tie to our past. It gives us insight into the moods of the world around us. It is a part of what is special about this national park. Enjoy it!
Did You Know?
Winds caused by changes in barometric pressure are what give Wind Cave its name. These winds have been measured at the cave's walk-in entrance at over 70 mph. The winds at the natural entrance of the cave attracted the attention of Native Americans and early settlers.