Black Gap Wildlife Management Area in West Texas recently won a special honor. It was designated a dark sky sanctuary by the International Dark-Sky Association. That indicates it has especially pristine night skies, and it makes an effort to keep them that way. It joins two other dark-sky sites in that region, which still has some of the darkest nights in the country.

Dark skies are getting harder and harder to find across most of the United States, though. As the population grows and cities and towns expand, the night sky is filled with more and more light. That drowns out the view of faint stars, the Milky Way, meteor showers, and more. It can interfere with bird and turtle migrations and other wildlife movements, and cause health problems for people.

Local regulations sometimes help. They limit the types and placement of outdoor lighting. Some cities have adopted streetlights that cast less light into the sky while also using less electricity.

And you can still find some fairly dark skies in many regions — even not too far from cities. The Dark-Sky Association has certified scores of dark-sky sites across the country. And many state and national parks are far enough from city lights that they offer good views of the night as well. Many of them offer skywatching programs to help you navigate those dark skies — an increasingly rare treat for much of the American public.

Tomorrow: looking for dark areas on the Moon.
 

Script by Damond Benningfield

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