Streetlights + Sky Glow


Above: sky glow above Calgary

Image credit: Royal Astronomical Society of Canada,

In urban spaces, we have almost lost the natural night, sacrificed to a slow onslaught of radiant sky glow. Though artificial light has immeasurably contributed to the enlightenment of humanity (both literally and metaphorically), collateral damage has included a gradual disappearance of the cosmos. With the growing prevalence of outdoor lighting, the stars are falling behind a hazy veil of light pollution. In Calgary (as in most North American cities) the night is in retreat, beaten back by the brilliance of car dealerships, casinos, skyscrapers, stadiums, blinking advertisements, headlights, LED streetlights, and so on. As constellations in the sky above are severed from stargazers below, as birds and insects fly in ever more feverish circles, and as some of the earliest mythology of mankind is removed further from the context of everyday life, we are forced to wonder: in losing the stars, what is it we’re really losing?


Above: tangible effects of sky glow, as illustrated through the 2003 Northeast Blackout in the United States

Image credit: International Dark-Sky Association,

24 The Deep Dark in Dawson

Above: The Deep Dark, as installed in Dawson City, Yukon (2015)

While much of our work has been oriented around illuminated objects, in pursuit of balance between perceived opposites, we’ve re-discovered the dark. In doing so, our eyes have been opened to an invisible world of subliminal triggers, nuanced habitats, public intimacy, real + imaginary dangers, and radical interconnectedness. The transformation of the same space from day to night is like a shifting of universes – a convenient analogy for theories of a stacked multiverse from the standpoint of our limited human awareness.

Connotations of darkness vary dramatically from wild spaces to metropolitan centres. Understanding the evolving role of lighting infrastructure within cities is complex (as a tangent, if you’ve ever been interested in learning more about early public lighting emulating the natural moonlight, listen to this podcast from 99% Invisible). Early lighting systems via candlelight and kerosene were implemented in larger urban spaces many centuries ago (areas of the Middle East supposedly installed casual public lighting as early as the 4th century, while London implemented public lighting between the 1400-1500s, with Paris following in the 1600s*).


Remarkably, when electric lighting was first introduced to public spaces on a wide scale in the 1800s, it was the subject of much speculation from philosophers and citizens. “People who witnessed the transformation were awestruck,” writes Christopher Dewdney in his transcendent novel Acquainted with the Night, “More than any lighting technology that preceded it – candles, oil lamps, or gas lighting – the electric light revolutionized the night. Now the darkness, at least in cities, was in full retreat.”

The physical and psychological effects of electric lighting on public space has changed post-sunset cities forever. But the advent of the LED light bulb, and the subsequent move towards utilizing LEDs instead of high-pressure sodium bulbs for street lighting, has changed the game again.


Above: Before (sodium halide) & After (LED) streetlight photos of streets in Hawaii

Image credit: The Hawaii Independent, 

In an effort to modernize infrastructure and maximize funds, the City of Calgary has been replacing traditional cobra head streetlights with sleeker LED models. The resulting transition from orange to blue-white light has been fascinating to watch, especially as it wicks new colours into the city environment. While LED lighting boasts increased efficiency, visibility, and adaptability (qualities not to be underrated, as dexterity has long been missing within public lighting) the spectrum of light emitted by LEDs purportedly has a more adverse affect on natural ecosystems than the monochromatic spectrum of high pressure sodium bulbs (LED Light Pollution: Can we save energy & save the night?)

Additionally, according to a series of compelling LED streetlight factoids published by the International Dark Sky Association, the economic efficiency of LED streetlights typically results in an overall threshold increase in brightness per lamp. And while an increase is light is often mistaken for an increase in safety, contrary to popular belief, an international study adapted by the Calgary Police “did not reveal statistical evidence which would support increased criminal activities resulting from decreased lighting levels.” Rather, “relevant literature also suggests that while improvements to street lighting have been shown to be a popular crime prevention measure, and to reduce the fear of crime, they have not typically been proven to reduce crime.” (City of Calgary Streetlight FAQ).


Above: image taken from Rothney Observatory in Calgary, showing the effects of light pollution

Image credit: Royal Astronomical Society of Canada,

This potential increase in brightness affects a variety of environments, but one of the most visible connections that has been disrupted (further) is everyday Calgarian’s relationship with the night sky above. If we aren’t thoughtful about public and private outdoor lighting alike, we will literally out-glow the stars.

Despite this, we remain aware and optimistic about LED lighting in Calgary. According to our associates with the City of Calgary Street Lighting department, since the introduction of LED lamps, road visibility is higher and vehicle/pedestrian collisions have gone down in Calgary since LED streetlights were introduced. LEDs are a clever technology and innovative minds will inevitably latch onto the benefits of adaptable light levels (ie. dimmer, more even, more site-specific lighting that allows natural adaptations in the eye to adjust to increased darkness). Additionally, commercial venues – especially car sales lots – should be charged with taking responsibility for their light bleed (some “Bright Sky Policy” advances have already been made in this direction, but none are retroactive, and many businesses seem to blatantly ignore light pollution as an issue).

Still, sky glow is a public problem, and as such we’re curious about what the transition from high pressure sodium to LED streetlights will mean for the streets, parks, rivers, public spaces, and people of Calgary? How does this seemingly minute shift in darkness impact the subliminal nuances of our nighttime environments? And how will this transition change our relationship with the universe?

Ever the opportunists, as we first began observing the adaptation of Calgary streets from High Pressure Sodium bulbs to LEDs, we became curious about what happens to the old infrastructure: where do streetlights go to die?


Above: 32,000 decommission Calgary streetlights, awaiting recycling.

In sleuthing out the answer to this question, we had the good fortune of working with various departments at the City of Calgary on an unrelated permanent Public Artwork we are building (scheduled for install over the next year or so). Our friends behind the scenes connected us with the Street Lighting department, and the people there were kind enough to bring us on a tour of the motherload of all infrastructure graveyards: a lot where 32,000 decommissioned streetlight heads await recycling for raw materials.

It is here, considering Sky Glow balanced against new civic infrastructure, that we first conceived Monument to Fallen Stars, a work commissioned by Downtown Calgary for the inaugural GLOW Festival this February. This is the first of five new works we anticipate completing in 2017, and we look forward to carrying you with us on those adventures. In the meantime, stay tuned…


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