When was the last time you remember seeing a star-filled sky? Have you felt like you’re not getting a good sleep at night? It may all be one problem: light pollution.
The explosion of artificial lighting over the past 140 years brought the benefits of productivity and convenience. But it also permanently illuminated the sky, pushing the darkness of night further and further away from human settlements.
And, as it turns out, darkness is very important.
Light pollution disrupts migratory navigation, mating rituals, hunting, and many other processes essential to the life of plants, insects, and animals.
Even worse, light pollution ruins our sleep. It interferes with the human body’s ability to produce melatonin—a crucial chemical that needs near perfect darkness to be generated. Exposure to light at night has been linked to diabetes, obesity, breast and prostate cancer, and other health conditions.
That’s why it’s worrisome that more than 99 percent of Americans live under skies considered light-polluted. And that’s also why about four out of five Americans can’t see the Milky Way anymore.
Gavin Heffernan and Harun Mehmedinović, visual artists and filmmakers, ran into the problem of light pollution through a hobby. They like to take pictures of the night sky, especially pictures with extremely long exposure, which can reveal many more stars than the human eye perceives.
But to get a clear shot, they found out they needed to move further and further away from civilization. City lights could ruin their images from hundred miles away. And the ongoing switch to LED lights adds to the problem, as they often come in a bluish hue which is more polluting.
Finally, Heffernan and Mehmedinović set up a Kickstarter campaign for a project to document the remaining islands of truly dark night skies across North America. Not only to capture their beauty, but also to raise awareness about their gradual disappearance “so that people recognize it’s a resource and endangered resource,” Heffernan said.
They have just finished the project and are publishing a photo and video book called “Skyglow.”
Over the past three years they traveled over 150,000 miles, collected over 500,000 photos, and learned a great deal about the impact of light pollution.
“What we learned is that it actually is potentially far more damaging than we think,” Heffernan said.
“For example, the trees are getting fooled into thinking that it’s the wrong time of year so a lot of the trees start budding weeks early, and when the trees start budding weeks early, then the insects start breeding weeks early, and when the insects start breeding weeks early the birds don’t have the insects to eat. … There’s just a very fragile balance that we’re discovering that is being lost by this night sky being taken away.”
They hope their book will encourage people to counter the ongoing trend of artificially turning night into day.
“We’re starting to learn that that’s just not good for us,” Heffernan said. “There is something in our fabric that we’re more and more losing. We’re kind of losing this connection with the night sky.”
Here are a few tips on how to reduce light pollution:
- Use fully shielded light fixtures. That means lights that shine down, not up into the sky. You can also urge your local officials to modify street lights this way.
- Install timers, motion sensors, and dimmer switches and turn off lights when not in use.
- Use lights with a red or yellow tint to minimize negative health effects and reduce impact on the night sky. Avoid blue light at night, be it from LED lights, TV, phone, or a computer screen.
- Keep your blinds closed at night.
- Don’t use more light than you need.
Tara McIssac contributed to this report.