Natural Bridges is World's First Dark-Sky Park
I can remember the first time I saw the Milky Way in the sky. It wasn't until my time in college, when I took a camping trip into the desert, that I could finally gaze up upon that misty cloud in the clear night sky. Don't get me wrong, I had seen stars before, and they were cool. I could easily pick out the Big Dipper and Cassiopeia from the sky above my city growing up -- probably because they were the only stars I could see on any given night. What I remember most about that night I saw the Milky Way, was that my familiar landmarks in the sky were gone. The Big Dipper had been swallowed up, it was now living among an ocean of other stars that I had never seen before. I hadn't known what I was missing until that night.
I'm quite happy to report some good news from the National Park Service regarding their efforts to conserve the natural dark sky. Natural Bridges National Monument, in the southeast corner of Utah, has been named the world's first ever International Dark-Sky Park, as designated by the International Dark-Sky Association. This is a big deal. It is a designation which recognizes not only that the park has about the darkest and clearest skies in all of the United States, but also that the park has made a every effort to conserve the natural dark as a resource worthy of the fullest protection.
The park, with the help of the little-known NPS Night Sky team working out of nearby Bryce Canyon National Park, identified every single exterior light within Natural Bridges. Based on an evaluation, each and every light was either eliminated or replaced with fully-shielded lights, some even equipped with motion sensors to reduce their light pollution even further. The Natural Bridges night sky conservation efforts include campfire interpretive programs and publications for visitor education about this seldom considered resource.
Chief Ranger Ralph Jones describes the unusually dark sky present over Natural Bridges: "The appearance to the naked eye of the Scorpius Milky Way easily fit Bortle's description for Class 2 with intricate detail resembling veined marble, and the sky being quite dark to within 15 degrees of the horizon in all directions. With these conditions a limiting magnitude of 7.1 or greater and a Bortle Class of 2 are reliably measured at Natural Bridges. This is a very dark and pristine sky worthy of aggressive protection and promotion."
I hope to see more parks work towards official dark-sky designations. It's an idea that has been considered before. As identified in the concluding remarks of a light pollution paper in 2001, the National Park Service was singled out as an agency that could lead by example for both energy and resource conservation by protecting natural dark skies.
Park areas that are both remote from large urban centers and are primarily wilderness parks should be identified as candidates for 'dark sky preserves.' The declaration of this type of status, even if only local or informal, could lead to increased awareness and reduced light outputs by residents and businesses of local small communities. The managers of park lands, especially 'dark sky parks,' should make every effort to reduce light pollution from in-park facilities and concession activities, setting the very best example possible for their neighbors.
The Milky Way isn't going away, but as human populations encroach on these once desolate parks, the ability to see that marvelous misty cloud in the clear night sky may disappear. I applaud the efforts of Natural Bridges, Ralph Jones, and the NPS Night Sky team to make the protection of this resource a priority.