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Boreal Community Media

Grand Marais considers Dark Sky initiative

Jan 05, 2018 07:05AM ● By Editor
By Brian Larsen from The Cook County News Herald - January 5, 2018

Astro-tourism might someday be coming to Grand Marais.

A committee has been formed to study what it would take for the city of Grand Marais to achieve an international Dark Sky Community (IDSC) status, said Grand Marais Mayor Jay Arrowsmith DeCoux at the city council’s Dec. 12 meeting.

What is a Dark Sky community? 

According to the IDA website, “An IDA International Dark Sky Community is a town, city, municipality or other legally organized community that has shown exceptional dedication to the preservation of the night sky through the implementation and enforcement of a quality outdoor lighting ordinance, dark sky education and citizen support of dark skies.”

Started in 1988 by Tim Hunter, a physician/amateur astronomer and David Crawford, a professional astronomer, Dark Skies missions are to preserve the nighttime environment from outdoor lighting that is not adequately shielded and which causes light pollution.

What defines light pollution? 

The IDA lists four types of light pollution. Glare, which is caused by the excessive brightness that causes visual discomfort; sky glow, the brightening of the night sky over the inhabited area; light trespass, where the light goes to locations where it is not intended or needed; and clutter, bright or confusing light and excessive grouping of light sources.

Among IDA’s concerns is that light pollution affects people’s circadian rhythm and may cause hormone imbalance. According to IDA, research has shown that in the last century, artificial light has reduced the periods of darkness that humans have evolved with over the millennia, and this has been linked to increased hypertension, attention deficit disorder, obesity, diabetes and some forms of cancer.

Then too, nocturnal hunters like a fox, bats, big cats and owls need darkness to hunt, and excessive light at night hurts their ability to catch food.

What does it take to become a Dark Sky community?

According to the International Dark-Sky Association, becoming a Dark Sky community is relatively simple. Communities agree on the right amount of light, in the right place, at the right time. These cities or towns set up and enforce outdoor-lighting ordinances and provide education to the public about the best places to put their outdoor lighting, so it complies with the IDA standards. 

Street lights, often a significant offender, are frequently changed to use as few lumens as possible and are cast down with shields to prevent light pollution.

Once a town or city has a plan in place, and it has shown exceptional dedication to preserving night sky, it can submit the proposal to IDA for certification. So far 11 cities and towns in the U.S. and five areas in Canada, Scotland, Denmark, and the Channel Islands have been certified Dark Sky communities.

The first step is to engage the community, local leaders, businesses, and residents to address their concerns and interest level in joining IDA sanctioned communities.

The committee tasked with seeing if Grand Marais will – or wants to – join other IDA cities and towns will follow a Dark Sky assessment which includes a mandatory audit of the lighting of the city. Several national organizations are available to help with an evaluation if needed.

As for astro-tourism, some communities are advertising their towns as Dark Sky compliant. Nature—trees, valleys, hills, and water—are featured areas even at night. One Colorado town set up a small observatory that attracts visitors from cities where the Milky Way isn’t visible because of light pollution. In those places, the Milky Way is but a chocolate, and caramel candy bar found on a convenience store shelf and not a jaw-dropping wondrous place to observe through a clear night sky.

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