By Nancy Tannler
Observing the night sky without the background illumination of city lights is a profound experience. Almost everyone has a fleeting memory of seeing the expanse of our solar system and witnessing this beauty.
Regrettably this experience is becoming unavailable to most people due to our overuse of incandescent light. Research is revealing that light pollution is affecting humans and other living beings both subtly and overtly.
In his book, The End of Night, author Paul Bogard explains how the gradual disappearance of true darkness is a loss for humans’ physical and mental health, societal relationships and ecosystems. Bogard writes about cities that have taken action to mitigate this problem and how we can too.
He points out that most people no longer realize that they have lost seeing the depth of darkness. We can observe a few of the brighter stars and planets and the moon, but we don’t see the sky lit up like when Vincent Van Gogh was seeing the deep blues and colorful stars depicted in his famous paintings. It’s a rare experience for us in the city to see our Milky Way galaxy.
The Bortle scale was developed in 2001 by John E. Bortle. It is a nine-level numeric scale that measures the night sky’s brightness. An example of Class 9 is the Luxo Sky Beam in Las Vegas, where only a few of the brightest stars, planets and the moon are visible since the sky shines with artificial light.
Class 1 allows us to see the constellations, Milky Way, the Triangulum Galaxy, globular clusters, etc. The only place Class 1 is available in America is at sea and west of the Rockies in southern Utah and the Oregon dessert. Most of us live in a Class 5 or above.
So why does this affect us? Beginning with the animals, “The overuse of artificial light ruins the habitat of nocturnal creatures,” Bogard said. “It confuses them; think of moths.”
Another example is sea turtles who have been laying their eggs on beaches forever. When hatchlings are born, they head towards the light, which until recently was the sea, although now, the glow of civilization has them heading in the wrong direction often becoming dehydrated, run over or handled by well-meaning humans.
There has been a controversy for years about why high-rise buildings blaze with light all night. Over 400 species of birds migrate at night and these buildings have proved to be hazardous to their flight because they are drawn to the light. In addition, it’s a waste of electricity.
Despite the bad rap bats get, they are one of our best bug catchers, especially of the unpopular mosquito. Studies show they are becoming disoriented and dying because they don’t know where they are in the light.
Thomas Edison’s discovery of the incandescent light in 1878 changed our lives an added hours to our day, keeping us safe at night. In researching his book, Bogard looked to history to draw conclusions about what’s different now with 24/7 light.
People went to bed in the dark, which could mean any time after 4 pm in the winter. So if they slept until dawn that could be 12-14 hours in bed. Most people don’t need that much sleep. So they would have what is known as “first sleep” and “second sleep.”
During first sleep, people would often wake up around two or three in the morning. Instead of lying in bed thinking they can’t go to sleep, people would get up and do something.
Often they would go out in the night and visit with neighbors who were also awake. Bogard points out that this is still going on in Africa to this day – people being out and about late at night.
After a few hours, they would head back to bed for “second sleep” and then get up in the morning as usual. In today’s world when we wake at 3 am, we call it insomnia and treat it as such. Bogard thinks it might just be an inherent reversion back to first and second sleep.
Melatonin is responsible for controlling our sleep-wake cycle and is only produced in the dark. The lack of it causes insomnia and that, in turn, exacerbates physical and mental health disorders with diabetes, obesity and depression on the top of the list.
Being in light all the time confuses our Circadian rhythms too, a natural internal process regulating our sleep-wake cycle every 24 hours.
Glaring streetlights, yard lights, billboards, office buildings and interior lighting beam bright every night. Despite all of these, we are beginning to learn about light pollution.
People rationalize the reason this is necessary is to stay safe. It has become our misconception that more light means more safety. Recent statistics reveal this isn’t necessarily so.
Most petty crimes, ones we predominantly light up for, occur during the day in big cities, while more serious crime happens at night. While Bogard does not suggest a return to the completely unlit nights of centuries past, he does make a strong case to carefully consider where and how light is deployed in order to provide sufficient nighttime illumination for safety without creating glare and other unwanted effects.
The International Dark Sky Association (IDA) was founded in the US in 1988 when founders David Crawford and Tim Hunter first recognized there was a problem. Since that time there are 103 IDA protected areas in the world. The awareness is growing.
Cities around the world are beginning to rethink street lighting, especially since many are switching from incandescent to LED lighting.
One important choice is the color of the light, white or yellow. Amber offers enough light to see by but does not release as much light into the atmosphere. It shines more like twilight.
Small things the rest of us can do is make sure our porch and yard lights are shielded, choose IDA approved light fixtures and bulbs and set an example by turning off lights.
As one naturalist said, the sky is “the world’s largest cathedral.” We could all go to church every night just by changing how we light up.