Bonnie Tsui is a contributing writer to CityLab. She writes frequently for The New York Times and is the author of American Chinatown: A People's History of Five Neighborhoods.
A new film explores what we lose when light pollution cancels out the night sky.
I remember the first time I went camping. I was 12 years old, and my swim team went on a rafting trip to the Delaware Water Gap. We got into camp in the dead of night, and I was blown away by the brightness of bodies in the night sky. I’d grown up well inside the nimbus of artificial light surrounding New York; what I remember most vividly is the feeling of disorientation as I stared up at the jam-packed firmament, streaked by the fluid, wispy smoke of the Milky Way, all of it animated from time to time by the fiery trail of a meteor. That looks so fake. Are those really all stars? How could there be so many up there, and how could I not have known about them until now? The unpolluted night sky, to me, was a revelation.
Filmmaker Ian Cheney had the opposite experience. Growing up in rural Maine, he saw the unfiltered night sky as a friend, a familiar, map-like indicator of home. It was only after he’d moved to New York as an adult that he started thinking about his connection to the night sky, and what happens when we as a species lose the reality of night - indeed, of darkness - in our daily lives. In a new documentary that's making its way across the country, The City Dark, Cheney takes a thought-provoking and lively look at the disappearance of darkness across our planet and the disruption of our natural cycles of light and dark.
Cheney, who won the Peabody Award for his 2007 documentary, King Corn, started pondering the curious loss of darkness in our 24/7 consciousness when he heard that the world population had tipped from being a majority rural population to a majority urban one.
“That got me thinking about the fact that, for the first time in the history of the planet, most people were now growing up in places where they couldn’t see an unpolluted night sky,” says Cheney. That shift from rural to urban mirrored his own shift from childhood to adulthood, and living in New York City. “So what does that mean? The night sky is just one part of what we give up from moving from countryside to city.” It was only on the journey of making the film, he says, that he came to understand all the myriad ways that artificial light affects us humans and the planet we inhabit.
In the film, Cheney consults historians, astronomers, and astronauts - people with rarefied experience with the cosmos - but he also talks with people who are familiar with the effects of artificial light on our ordinary everyday: the owner of a lighting store; a Boy Scout troop leader who brings city kids to the woods; a wildlife veterinarian who deals with disoriented birds; a lighting designer; a criminologist who studies how installing bright lampposts reduces urban crime.
When Matty Holzhacker, the Boy Scout troop leader in New York’s Washington Heights, brings his kids camping, they are astounded. “Oh my God—there’s like a hundred stars,” says one boy. (At one point during the film, Cheney himself counts out measly handfuls of stars at various locations from Battery Park and Times Square to Harlem and Staten Island.) But more profound is the sense of the larger world they get from the view—that there is a lot more out there, and more hours in a day to enjoy it. “Time goes slower,” another boy says, wonderingly.
“Our shift to being an urban population raises a lot of questions about our relation to nature,” says Cheney. “The modern environmental movement took hold only when we started to lose a connection to the natural world. Perhaps so, too, with light pollution. But maybe what matters is what we gain—and what we do—when we do in fact see it.”
Neil deGrasse Tyson, the prominent astrophysicist, tells Cheney a story about growing up in the Bronx and visiting the Hayden Planetarium for the first time. He remembers thinking that the night sky portrayed in the dome was a hoax. “To this day, I’m on mountaintops, and I look up—and this is a sickeningly urban thing to say—and I say, ‘Reminds me of the Hayden Planetarium.’”
One of the major ideas in The City Dark is that it’s easy to forget the scale of our world in the universe if you never get to see the night sky and all there is in it. Nowadays, Cheney says, you have to go farther and farther to get closer to the universe. He seeks out astronomers on the summit of Haleakala, one of the most isolated spots in the world, thrust up above the cloud cover on the Hawaiian island of Maui. Scientists there are on the lookout for killer asteroids en route to Earth, but they also ponder a deeper loss with the ever-encroaching fog of light from cities below.
“If we lived on a planet that was forever opaque to the universe beyond, science and inquiry would have been terribly distorted and twisted,” says Jeff Kuhn, a University of Hawaii astronomer, in the film. “In my lifetime, we once believed that there weren’t any other planets except for the planets around our sun, and because we could look out into the sky and we could see the universe, we now have a very different picture of a universe that’s filled with planets… to close that door, I think, would change the character of humankind entirely.”
And it’s more than just humans who are losing the night. Nature is, too. Footage of just-hatched sea turtles trying to find their way to the ocean in Florida is one of the more heartbreaking scenes in the movie, when the disoriented hatchlings head toward the bright light of nearby apartment complexes instead of toward the moonlit water.
Light changes habitat just like a bulldozer can. In the film, Cheney says that he sleeps better up in Maine, positing that in New York he misses not just the stars in the night sky, but the dark that comes with it. From talking with leading epidemiologists and cellular biologists, he finds that the health effects of 24/7 light can be severe; studies have found almost double the incidence of breast cancer in night shift workers, and evidence points to disrupted circadian rhythms from exposure to light at night. He discovers that the World Health Organization has identified night shift work as a probable carcinogen.
One of the most gripping sequences in The City Dark involves astronaut Don Pettit taking photos from the space station, of the galaxies of light that we have created on our planet. “I was struck by Pettit’s affection for the night sky - it goes hand in hand with the affection he feels for the cities, and city lights, of the planet when he’s up at the space station looking down, missing home,” Cheney says. The constellations in the sky parallel the constellations we have created here on Earth. And even though it may feel like a lost cause, every star we bring back to the city makes a difference, and it can be done - and indeed, has been done - through more thoughtfully designed urban lighting. Though we might love the light, we also need the dark. In this meditative, illuminating film, Cheney asks, Why can’t we have both?
All images and video clip courtesy Wicked Delicate Films.