When artificial light shines upward, it bounces off particulates in the air, causing a haze — some have described it as a “luminous fog” — that prevents us from seeing the stars and skies above. As our powerfully-lit built environment expands across the planet, so does this dome of light. Astrophysicist Neil deGrasse Tyson contends that a connection to the night sky offers us a sense of “cosmic perspective” that, when denied, causes us “to not live to the full extent of what it is to be human.” The stars have inspired mythology, poetry, curiosity, inquiry and exploration throughout history. So, what happens when we lose the night sky? That question is at the heart of The City Dark, a new documentary film by Ian Cheney that explores the effects of light pollution on our environment, our society, our bodies and our psyches. (See the trailer here.)
The most obvious implications of light pollution are to astronomers. The stronger the light pollution, the harder it is to see the universe beyond. But, as Cheney explores in the film, the consequences of our pervasive use of artificial light reach much further. Biologists who study habitat disruption are tracking how city lights disorient, and ultimately cause the death of, hatching sea turtles and migrating birds. Epidemiologists are investigating the hypothesis that night shift work, and the disruptions to circadian rhythms and melatonin production that come with it, is a carcinogen.
But light activates space, improves public safety and facilitates social interaction. Light is used as art, as celebration, as tribute. We equate light with progress and achievement. So what do we do when, as Cheney says, “though we might love light, we might need the dark”? That’s where lighting designers, architects and planners can help. A darker city can come from, not just less light, but less wasteful light. Careful, thoughtful lighting design is economically and environmentally beneficial, and can help reconnect us to the majestic skies above.
Tonight, Wednesday, August 17, The City Dark is being screened at the BMW Guggenheim Lab in New York City. In anticipation of the event, we sat down with Ian Cheney to learn more about light pollution, the disappearance of the night sky and what we can do to get it back. —V.S.
Tell us about The City Dark.
The City Dark is a documentary about light pollution — which ought to be called night pollution, if you think about it. Air pollution is pollution of the air, water pollution is pollution of the water and what we are really talking about is pollution of the night by light.
I have found that light pollution as an urban and environmental concern isn’t a topic on everybody’s radar screen. But once one mentions the disappearance of the night sky, people instantly connect. There’s something so fundamental and present to all of us about that.
Throughout the film, evocations about the poetry and mythology of the night sky interweave with scientific inquiry into the effects of artificial light on ourselves and our environment. Though a complete telling of the story seems to demand both poetry and science, did you come to the subject matter from one side or the other?
The film began much more with the intangible questions and what I might categorize as the more philosophical or spiritual question about what we lose when we can’t connect with the night sky. I knew next to nothing about most of the ecological or human health issues related to light pollution. But I knew that astronomers, of course, were worried about the loss of the stars. So it was with them that we started the film. The astronomers were the ones to point out that this topic touches a much broader range of people. But even as the film snowballed into explorations of the scientific issues, there was no way to tell the story without the intangible aspects. What we lose as individuals, as a culture, when we lose the night sky is what underpinned the whole project for me.
Is that what you hope people with take away from the film?
I’d be happy if people took different ideas away from the film. One person might be energized by the idea of writing a new lighting ordinance for their town and introducing legislation that helps preserve the night sky, whereas another might be reminded to step outside and look up from time to time, to take his kids outside the city to find darkness, or to think differently about how to design lights on a building.
We are setting up a lot of screenings this fall with a whole range of people, from astronomers to ecologists to wildlife groups, but also with lighting designers and architects who are very much engaged in rethinking the way we light our cities.
Speaking of which, in the film you say “a darker city is a matter of design.” You also spend some time with Hervé Descottes, the lighting designer of the High Line. Talk a little bit about the design of a darker city, and the role that architects and designers can play in preventing light pollution.
The way we have come to light our cities, perhaps unintentionally, is extremely wasteful, haphazard and careless. The idea that light can trespass, can pollute, can be damaging, is relatively new. Maybe because you can’t hold light in your hand like you can water or garbage — if someone were spewing garbage into your window, you would object.
There’s a fair bit of generalizing and mudslinging directed towards architects and lighting designers by people who think they all just love to blast light up their buildings. Some do, and you see that walking around the city, but there are an increasing number of lighting designers that are trying to do things differently.
It’s not that advocates of “re-darkening” the city want to turn off all the lights. Hervé Descottes is one of, hopefully, a growing number of designers who are thinking about light in a more sophisticated way than we may have in the past, when we were responding to a centuries-long legacy of having too much darkness and seeing more light as better. His approach to lighting design is as much about celebrating the darkness and the shadow spaces as it is about the beauty of light. Whether that comes from a respect for the beauty of the night sky, a regard for people’s melatonin levels or aesthetic choice, I think it’s a profound and interesting shift in the way we think about lighting cities. It may seem ironic that a lighting designer would be talking about the need to use less light, but fortunately lighting designers aren’t paid by how many lumens of light they use in a design.
The International Dark-Sky Association has done a lot of wonderful work in helping people rethink the way we light our spaces, from introducing and modeling lighting ordinances to conducting nuts-and-bolts research on fixture design and how light affects space. There are so many strategies and technologies available to people that I think suggest a promising future. It’s similar to the way we talk about green design — in fact, smarter nighttime lighting is a LEED green building point, which is a sign that people are recognizing that lighting our environment means more than just the loss of the stars. We can use better lighting as a way to create different and, in the end, more livable spaces, where people will be able to sleep better, birds can find their way and we can connect to the stars.
You spend some time in the film talking about the enormous cultural impact of light. Light is used as art, as celebration, as tribute. Light is equated with safety, with social activity, with progress, with development. With light so often linked to positive notions, when and how did the idea of light pollution, and the need to “re-darken” the city, take hold? And does the cultural significance of light present obstacles to popular acceptance of light reduction?
It’s fascinating — even though the recent attention to light pollution paid by groups like the Dark-Sky Association is new, the idea that people think their city is over-lit is not. The introduction of new lighting technology has always made people long for the way the city used to be. When arc lighting and electric lighting were introduced in the late-19th century, people were immediately nostalgic for the quiet, orange glow of the gas-lit city. In the film we speak with Bill Sharpe, a historian of the way people wrote and created art about the night in New York City, whose book New York Nocturne documents some of the rich history of that nostalgia effect. But today, people dismiss that nostalgia as overly romantic because it looks back to something none of us have experienced. We’ve had electric lighting for over a century.
As you mentioned, there is an involved relationship between light and safety or crime. People feel safer in well-lit spaces. But when you start getting into the data about whether introducing light alone will consistently make a neighborhood safer or not, there are instances where it does and instances where it doesn’t, where light just moves crime elsewhere or even makes it easier for criminals to operate. But it’s inarguable that people continue to feel safer in the light. I suppose it’s in our genes. We don’t see as well at night — though we can see and navigate through shadowy space better than we think. It’s a complex issue, one that I only touch on briefly in the film.
What are some other ways that people are addressing light pollution through technological advances, legislation or individual action?
The way people are starting to rein in the light runs the gamut. There are volunteer measures, such as In New York City, where some people have signed on to shut off lights in buildings or on bridges at certain times during migration season. Then there are cities like Tucson, Arizona, where you can see the Milky Way from downtown because they have such a robust lighting ordinance.
Many lighting ordinances are designed to be gradual and realistic about what is expected of the community. They don’t require everyone change their lights immediately, which would be quite costly, but any new lights that are introduced have to be cut-off lights, which direct the light downwards, to the ground, where you actually need it, rather than through someone’s windows or up into space. Which is almost a boringly obvious idea, to not waste something.
When you get right down to the nuts and bolts of better lighting, it’s pretty easy to grasp, even if implementing those ideas isn’t always easy. It involves years of wrangling, because there’s money to be made burning fuel to waste light, and there’s an instinctive resistance to reducing the way we light. It often goes back to the question of crime that we discussed earlier. People think that if the city turns off lights, crime will follow. It’s instinctive.
New York City and New York State have seen their fair share of lighting measures introduced and failed time and again. Maybe a city like New York seems like too much of a lost cause, maybe there are other things to worry about, or maybe there’s real pressure coming from people with an interest in maintaining the status quo. But whatever the reason is, those efforts haven’t been able to gain traction as more than volunteer measures.
As you travelled from city to city, region to region, did you see differences in the way more vertical cities were tackling these challenges as compared to more sprawling cities?
This is a bit of a roundabout way to answer your question, but it ties in with how we think and talk about wilderness and the environment. Environmentalists and conservationists are often arguing about where to put our money and energy – should we conserve and preserve fenced-in parks as pure wilderness, where urban residents can visit to enjoy trees, bugs, birds, ponds and stars? Or — and it really shouldn’t be an either/or — should we put our energy into making the spaces where we live every day that much more green and livable? At the end of the day, there are limited resources and one has to figure out where to put one’s efforts.
That same debate applies to light pollution and the disappearance of the night sky. In a city like New York, should we put any effort into restricting lighting given how few stars we can see? Or should we put more energy into the suburbs, where you have at least a fighting chance of seeing the Milky Way? Or should we dedicate ourselves to preserving rural skies, where both urban and suburban residents can escape to see the night sky? Of course, I think all should be done.
But I do think bringing back even one more star to a city sky is worthwhile. Maybe that one star — and I’m paraphrasing a comment by Neil deGrasse Tyson that didn’t make it into the film — will be the star that catches some young scientist-to-be’s eye and enthralls him or her with the idea of becoming an astronomer. Or connects someone with the idea that there’s a larger world, which I think ultimately is the most important thing. The most profound risk we’re taking by losing the night sky is becoming a completely downward-looking species.
There’s something mesmerizing and unparalleled about a truly dark night sky. It’s hard not to get really cheesy, really fast when talking about it. And, just like seeing the Grand Canyon or a great whale, there’s something different about experiencing it yourself than seeing it on a television screen or in a magazine. But Neil deGrasse Tyson’s story of discovering astronomy through the planetarium, because he never saw the stars from his home in the Bronx, is a great example of how, on the one hand, the proxies we create for wilderness experiences, whether it’s Central Park or planetariums, are meaningful and important. Tyson wondered aloud whether, if he’d grown up on a farm, seeing the night sky every night, it would have inspired the same sense of awe that it did for him, having grown up in the Bronx.
As the night sky recedes from view, what do you think it means for our collective imagination, curiosity or inspiration? What happens when we don’t have access to that sense of awe?
It’s an experiment in progress. We’re doing this to ourselves. As a country, and now as a world, as we tip towards being a dominantly urban population, we are mostly growing up without the stars. On some level it remains to be seen what it will do to us. This whole film was in a way my own attempt to engage with some of those questions. I certainly don’t have all the answers.
I think we all gain wonderfully different things from our experiences with the night sky. For me, it has been a profound reminder of our place in space and a perspective on my own moment in the lifetime of the universe. It has made me really value what time I have on the planet, but I think that’s probably not a bad thing to value and to keep in mind, how remarkably unique life on the planet is.
At times the environmentalist community and the astronomy community have been at odds with one another, arguing about whether limited financial resources should be dedicated to cleaning up our mess here on this planet or exploring elsewhere. But I think the more we learn about outer space, our place in space and our relationship to the stars, the more it makes us careful citizens of the planet. That, weirdly, was one of the things I was most interested in exploring in the film – I don’t think it actually comes through very much at all, but so it goes. But I do think that the more we see the stars the more we actually care about our planet.
Are there other topics you wanted to explore further than didn’t make it into the film?
Sleep science. I would love to make a whole film about how we sleep. There weren’t really sleep scientists before the industrial revolution, so we don’t know that much about how we naturally sleep. Experiments have been done where people are locked away for weeks at a time to see how they sleep “on a natural cycle.” The results echo how sleep patterns used to be described in literature — people often sleep in two segments of time, waking up once in the middle of the night.
There is so much about a city that is a shock to the human immune system. Think about what you learn in seventh grade: animals exist in habitats and if you disrupt those habitats, the animals suffer. And yet somehow we don’t turn that same attention to our own habitat.
I realized — and I never used to think of it this way — that we keep exploring this question of disrupted habitat from different perspectives through our films. In King Corn, we looked at the way we eat and how it’s completely out of whack with how we’ve evolved to eat. With The Greening of Southie, a film about green building in Boston, we explored the physical spaces we find ourselves living in. And now we’re looking at this question of how we light our world and how it represents a real disruption in our circadian rhythm. We’ve evolved for many, many generations with certain cycles of light and dark. It’s very interesting to live in an urban environment and think about how can we design spaces to give us the things we want out of a city, which are many, and yet not make us sick or unhappy or solipsistic in the process.
Really we just take these recklessly boring topics like watching corn grow and watching buildings go up and star gazing — its not blockbuster stuff — and we try to suggest ways that they are fundamental to our lives.
For the film, you developed a letter-grade system for rating star visibility in different locations. Sky Village, Arizona (?) received an A; Times Square an F. The highest grade for NYC – at least of the areas you list in the film — is a C+ (Staten Island). Did anywhere in New York City get a better grade? Are there any secret corners that are still good for stargazing?
I bet there are places in New York City that can rock a B—. Maybe Floyd Bennett Field? That’s where all the astronomers go. There’s also a wonderful guy named Jason Kendall who runs an astronomy program up in Inwood. He leads groups, does stargazing and meteor-gazing there.
What’s next for Wicked Delicate Films?
We got a little development grant from SilverDocs, in partnership with Whole Foods, for a film called BlueSpace, which will be a film about urban waterways around New York City. We’re looking at the idea that the city’s waterfronts and harbors — its “blue space” — should be considered as powerful and important a resource as its green space. I’m infatuated with that idea, especially given the city’s history of thinking of our water as a toilet. We’re just digging into that.
