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2014 is Flagstaff’s Year of the Night Sky!

A Protected Night Sky over FlagstaffWhen the great earth, abandoning day, rolls up the deeps of the heavens and the universe, a new door opens for the human spirit, and there are few so clownish that some awareness of the mystery of being does not touch them as they gaze. For a moment of night we have a glimpse of ourselves and of our world islanded in its stream of stars – pilgrims of mortality, voyaging between horizons across eternal seas of space and time. Fugitive though the instant be, the spirit of man is, during it, ennobled by a genuine moment of emotional dignity, and poetry makes its own both the human spirit and experience.

Henry Beston, The Outermost House (1928)

A dark, star-filled night sky is often thought of as important for astronomy or research. Though this is true, the grandeur of the night sky is much deeper and broader, and accessible to anyone. We find the beauty and meaning of natural night is best expressed by poets and writers, such as Henry Beston, Rachel Carson, and Paul Bogard.

Grand CanyonPhoto by Tyler Nordgren, courtesy of the Grand Canyon Association

Flagstaff Dark Skies Coalition

Our Mission: To celebrate, promote, and protect the glorious dark skies

of Flagstaff and Northern Arizona through successful dark sky practices.

 

Although astronomers and astronomy are important (some of our best friends are astronomers), protecting the night sky just for astronomers would be like protecting Grand Canyon just for geologists. Yet no one ever seems to think so narrowly about the Canyon; it is our hope that after looking through our website you may think more broadly about the night sky.

 

As the international dark sky movement began in Flagstaff in 1958, our community has always been keenly aware of the special value of the night sky. The Flagstaff Dark Skies Coalition and the greater community of Flagstaff are proud to remain world leaders in practical and successful dark sky protection.
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Recent Posts

Lights Out Flagstaff Darkens the Sky in Heritage Square

The Meter Moves!

Light Pollution drops dramatically

Light Pollution drops dramatically

On Friday March 28th at 7:43PM, in Flagstaff’s Heritage Square in the heart of downtown Flagstaff, the post-top lights owned by the City, as well as some nearby business lighting, were turned off, and remained off until Sunday evening. This was the beginning of the first Lights Out Flagstaff, and the kick-off for the 2014 Year of the Night Sky.

At the U.S. Naval Observatory table, they were measuring the brightness of the “sky” with a “Sky Quality Meter” (SQM).

The Light Meter Setup in Heritage Square

The Light Meter Setup in Heritage Square

When the nearby lights went out, the brightness measured by the SQM dropped dramatically – 90%! But the light meter was measuring more than just the sky. The diagram shows that the meter was aimed straight up, but was located close enough to one of the lights in the Square that it was catching a lot of light directly from it as well. The SQM they used is most sensitive to light coming from within ± 10° of the direction it’s pointed (in this case straight up), but it still has some sensitivity to light coming from even 90° to the side. Since the light was located only about 20-feet away, and was so bright, it produced the dominant signal in the meter, overwhelming the fainter sky overhead. Thus the 90% drop in the measure when the light went off.

So, though the sky brightness itself didn’t really drop by 90% (we think it was more like 10-20%), the dramatic drop in the brightness measured by the SQM is still a fair qualitative representation of how “light pollution” dropped because our eyes, looking up toward the stars, are also very sensitive to bright lights nearby (especially white ones). When the lights went out, the stars really did become dramatically more visible… and were enjoyed by many with their own eyes and using the telescopes hosted by Coconino Astronomical Society members.

The Universe over our heads (Brian Bradley Photography)

The Universe over our heads – photo taken just before the lights went out (Brian Bradley Photography)

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