College scientist takes on local light pollution
MIDDLEBURY — The winter solstice, which will mark the longest night of the year when it arrives this weekend, is often a time for ritual, reflection and spiritual investigation — not least because of the rich connections we have with darkness.
But the physical darkness at the heart of many of our traditions is slowly going away.
“If you’ve never seen a truly dark night sky, don’t wait too long — it’s getting harder and harder,” wrote astrophysicist Kelsey Johnson in The New York Times earlier this year.
Satellite imagery between 2012 and 2017 showed that global light pollution increased at a rate of about 2% per year, according to the International Dark-Sky Association. If it continues at that rate it will double every 36 years.
The same has held true in Addison County and beyond, which is why Jonathan Kemp, a Telescope and Scientific Computing Specialist at Middlebury College, has been working with students at the college’s Mittelman Observatory to conduct outreach and educate the community about local light pollution.
This isn’t just about stargazing, though.
“As an astronomer I, of course, want people to appreciate and preserve the night sky,” Kemp told the Independent. “But light pollution isn’t just an astronomy issue — or a biology or even a human issue. It affects all living things.”
Which may be the most important aspect of his outreach.
Light pollution, which is loosely defined as the inappropriate or excessive use of artificial light, has a number of negative effects, Kemp points out:
• It devastates wildlife.
• It may harm our health.
• It wastes energy and money.
• It robs us of our heritage.
• And it may very well be making us less safe.
Sensory ecology is, as scientific fields go, pretty new. It focuses on the information organisms get from their environment and how they get it.
For countless species, light is a significant source of information. It helps them know when to eat, sleep, migrate, reproduce and avoid predators.
And it can have deadly effects.
Sea turtle hatchlings are drawn away from the ocean by artificial light. Birds — millions of them every year — crash into brightly lit skyscraper windows. Insects, including pollinators, have seen population declines because they misread information presented by artificial light, according to a 2016 survey of studies published in Biological Conservation. This can affect entire ecosystems.
But it’s not just animals that are suffering.
HUMAN HEALTH & CRIME
“Artificial light at night is also associated with negative effects on (human) health, including a significant correlation with all forms of cancer,” wrote Johnson in the Times. “It affects our circadian clock, which is turn affects the production of melatonin, a hormone that plays a role in sleep.”
Johnson cited a recent study in the Asian Pacific Journal of Cancer Prevention that recommended taking “immediate measures ... to limit artificial light at night in the main cities around the world and also inside houses.”
Nighttime exposure to the “blue light” wavelengths — generated by electronic screens and most LEDs used for outdoor lighting — seems to be especially disruptive, because of their more powerful affect on the suppression of melatonin, suggests the Harvard Health Letter, a publication of Harvard Medical School.
In some ways, light pollution is also making us less safe.
“Artificial light at night can also create blinding glare from overly bright and poorly shielded outdoor lighting,” according to the International Dark-Sky Association. This can make driving, cycling or walking at night more dangerous. “Aging eyes are especially at risk,” the association notes.
But doesn’t more and brighter light at night cut down on crime?
“The analogy I like to use is a swimming pool,” Kemp said. “A pool needs chlorine to be safe, but you’re not going to add truckload after truckload of chlorine, because that would make the problem worse. It’s the same idea with lighting.”
“There is no clear scientific evidence that increased outdoor lighting deters crime,” Kemp says.
In some cases it might be the opposite.
Bright and poorly aimed lights can hide danger by creating contrasts between light and dark areas, which can be hard for the eyes to adjust to. Darker shadows make for better hiding.
At the same time, such lighting, particularly dusk-to-dawn lighting, may actually attract criminals, who can better see what they’re doing, according to research cited by the Dark-Sky Association.
Kemp is quick to point out, however, that safely lit spaces and dark skies are not mutually exclusive concepts.
“People often believe that it comes down to one or the other,” he said. “That light pollution is just a sacrifice we have to make for safety’s sake. But that’s not necessarily true. Dark skies don’t have to mean dark ground.”
On a municipal or even just a college-campus scale, mitigation of light pollution will require a broad and ongoing effort, Kemp explained.
In the short-term this might mean putting caps on outdoor fixtures; in the medium-term, replacing bulbs and fixtures; in the long term, creating ordinances and implementing best principles of lighting design, which include:
• Only light when needed.
• Only light where needed.
• Only light as much as needed.
• Minimize blue-light emission.
• Fully shield outdoor lighting and point it downward.
Using existing technology like dimmers and timers would not only protect our environment and our night skies, but they would also save significant energy and money, Kemp said.
The Dark-Sky Association estimates that light pollution in the United States costs $3 billion a year.
“This isn’t just about the observatory or the college, but about all of us protecting the common good for the community,” Kemp said.
With that in mind Kemp has developed a Dark Sky Survey, which he hopes will give his team a better picture of the local community’s perceptions about light pollution. The survey is open to everybody, on campus and off, and can be found by visiting go.middlebury.edu/darkskysurvey.
Kemp has also been working with a number of Middlebury College students to increase community engagement.
Kelly Zhou, a sophomore who grew up in Taiyun, China (population: 4 million), and Paul Ruffalo, a sophomore Feb. who grew up in New York City (population: 8 million), both described feelings of astonishment at discovering Vermont’s night skies.
“I was amazed and shocked by the macroscopic Milky Way when I walked up to the (observatory) dome,” Zhou said. “I realized what people living in cities have missed — the hidden beauty up in the sky and a tranquil nighttime.”
When Ruffalo heard that Kemp was looking for students to help out at the observatory, he immediately sought him out.
“I fell in love with the night sky and teaching my fellow students about it at events,” he said.
Oscar Psychas, a junior who has been working on an independent project at the observatory, tries not to take those night skies for granted, he said.
“There’s something amazing about suddenly looking up and seeing the Milky Way and constellations such as Orion, and feeling part of something bigger.”
When Psychas started noticing how so much of the college’s lighting design, especially streetlights, makes it difficult to see the stars from so many parts of campus, he reached out to Kemp and discovered that they had similar project ideas.
“I would be really excited to see many community members finding ways to steward and share the incredible resource of our night sky,” he said.
Local photographers Caleb Kenna and Jason Duquette-Hoffman enjoy shooting at night but also struggle with light pollution, they said.
“While the lights of the town are an integral part of the built environment, and can have their own part to play in the overall image, the ambient light they create also limits how much of the background environment that can be included in the image,” said Duquette-Hoffman, whose work accompanies this story.
Light pollution can make it hard to capture not only the built landscape but the wider universe around us, he explained.
“It feels kind of like a metaphor for our own short-sightedness — in so many ways.”
Reach Christopher Ross at firstname.lastname@example.org.