Light pollution: Sacrificing the stars for brighter streets
By Matt Tempesta
**In this video, Mike Hansen, a volunteer with the New England Light Pollution Advisory Group, discusses the effects of light pollution and ways to fix the problem.
If you ever find yourself in Maine on a clear night, take a look up and you'll notice a faint blue haze arcing across the sky. That's not a passing cirrus cloud, it's a ring of our Milky Way galaxy: hundreds of millions of stars, mixed with hot gas and celestial dust, stretching into infinity.
Travel a few hundred miles south and it's a different story. Walking around the streets of Boston at night, you'd be hard pressed to find more than a handful of stars struggling to shine through the massive amount of lighting.
But that may be changing.
This past summer, the towns of Andover and Milton voted to shut down half of their streetlights. But while this was mainly a money-saving measure, Andover selectman Mary Lyman said it's already made a difference in the night sky.
"It was based on money," said Lyman. "We had the safety officer and the highway superintendent go around town at night and identify lights that were not necessary for the safety of the street. It is much clearer in the school areas where we used to have massive lighting on the parking lots and the stars are much brighter."
According to the New England Light Pollution Advisory Group, there are two main types of light pollution: skyglow and light trespass.
Skyglow is the result of the countless upward-facing lights like this, in and around cities that drown out the night sky. It's the main culprit when it comes to loss of stars and is especially noticeable on cloudy nights, when the city remains fully-lit long after the sun has set.
Light trespass is the result over-lighting and improperly placed lights that impede on the surrounding environment. This can be as simple as a flood light aimed into your bedroom at night, or streetlights washing out stars in a nearby observatory.
"Nighttime lighting and exterior lighting is one of the larger energy costs particularly in municipalities in terms of electricity," said Mike Hanson, a volunteer with the NELPAG. "The other big thing is that we're seeing impacts on migratory fish (in streams and ponds) where fish won't move when it's brightly lit. It's been causing a lot of unnecessary deaths for migratory birds because of the distraction and confusion lighting causes the birds."
Some solutions to light pollution lie in the type of lighting fixtures used. Motion sensors and automatic cutoffs can help reduce the amount of time lights stay on. Then there's proper positioning, where lights point down instead of up, greatly cutting down on skyglow and light trespass.
But while some towns around Boston are taking steps to curb light pollution, Hansen said there's still a long way to go before real results are seen.
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