…So Why Aren’t We Listening?

Posted On March 10, 2018

The heavens are telling, so why aren’t we listening?

We look up and see the stars. From Earth orbit, we look down and see the streetlights. And under the streetlights, we can no longer see the stars.

In a recent post, I wrote about a few celestial events that I had witnessed and found awe-inspiring: a planetary alignment, a solar eclipse, and a lunar eclipse. These were easy to photograph; they were of large, bright objects – the sun, moon, and planets – that could be viewed by anyone almost anywhere. These bodies are the big players in our sky, but there is so much more to see, much of it invisible to us under our light-polluted skies.

Contemporary humans have the advantage of having binoculars, telescopes, and camera lenses to see things in the heavens that were unknown five-hundred years ago or less – things like double stars, the moons of Jupiter, and the planet Neptune. However, most of us are even cut off from the beauty of the night sky that the human race has seen without optical aid for most of its existence. A recent study has estimated that due to light pollution in our built-up areas, one third of humanity and 80% of Americans cannot see the Milky Way. I’ll go one step further: those of us who live in major urban areas can hardly even see the constellations. Only the brightest stars are visible to the naked eye in the city.

I have become much more aware of this since I have been trying to find dark-sky viewing sites in the last year or so. Increasingly frustrated and impatient with the sights available from my urban backyard and driveway, I began to search for better places to observe the night sky.

There are two main problems with viewing the sky from the city: stuff that blocks the view (buildings, trees, and so on) and scattered artificial light from streetlights, homes, and businesses. There is often some way to get a more-open view of the sky, like in a local city park, but this may not be where you want to go alone at night for safety reasons.

Light pollution is a harder problem to solve. John Bortle, an American amateur astronomer, devised a scale to describe the quality of dark skies for astronomical viewing. The scale, summarized in the table below, has nine levels, with Class 1 being the darkest.

Class	Description	How dark is it?
1	Excellent Night Sky	Brightest part of the Milky Way casts shadows.
2	Average Dark Sky	Details of structure are apparent in the Milky Way.
3	Rural Sky	Some deep-sky objects (galaxies and star clusters) are visible with naked eye.
4	Rural/Suburban Transition	Constellations are easily discernible.
5	Suburban	Most deep-sky objects are invisible to the naked eye.
6	Bright Suburban	Milky Way is visible overhead only.
7	Suburban/Urban Transition	Milky Way is invisible.
8	City Sky	Dimmer constellations are incomplete or invisible.
9	Inner City Sky	Only the brightest stars are visible.

In 2016, an international team of scientists led by Fabio Falci of Italy published The New World Atlas of Artificial Sky Brightness. Using satellite and other observational data, the atlas maps out locations of greater and lesser light pollution. Perhaps not surprisingly, the worst places are Western Europe and Eastern North America, although there is significant light pollution in most places where there are large concentrations of population.

Jurij Stare of Slovenia has combined information from the atlas, Bing Maps, the Bortle scale, and other data to produce an online world light pollution map. I used this map to look for reasonably close dark-sky sites. It was a bit depressing.

A portion of the light pollution map is shown below. That big open wound on the image is Winnipeg, my home. According to the data, I live under a Class 8 or 9 sky. I was recently just outside Beausejour, an hour’s drive from home, where the sky was substantially better, but still only Class 4. A retreat centre I go to at Victoria Beach is under a Class 3 sky. I have not been able to see the Milky Way at any of these spots, but I did get a very good look at the Pleaides and the Orion Nebula at the two darker locations. (With an 80mm refractor telescope I could see the nebulous haze around these two objects that I could not see in the city.)

Viewing is considerably improved within about an hour’s drive of home, but to get to a Class 2 sky is about a two-hour drive and a Class 1 sky is about a day’s drive away. Basically, viewing something under better than city conditions involves making a significant effort, requiring at least a couple of hours of travel time. Truly dark skies require an overnight commitment. And this is in a region that has been referred to as “the middle of nowhere”. (Those of us who live here know better, but OK, we are distant from other large centres.)

Even more appalling, when I zoomed out looking for dark-sky sites in Manitoba, I noticed a splotch of light on the left side of the map, considerably bigger than either Winnipeg or Minneapolis. What even is that? There’s nothing there! (This is what Winnipeggers unkindly think about North Dakota.)

The big light splotch turned out to be a large area settled into a bend of the Missouri River near Williston, North Dakota (population 26,000). A little more searching revealed this to be the site of the Bakken Formation, the large petroleum reserve that underlies the northwest corner of North Dakota. It was the light of the gas flares from the oil wells in the region.

We have obliterated dark skies in our cities, suburbs, and towns. To get to a place that is dark enough to really experience the night sky, we need to burn fossil fuel to drive there. The need for this fuel requires us to further extend the area of light pollution into a previously near-pristine area. This is potentially an ever-expanding cycle.

What has this done to us? The skies that once guided our understanding of the seasons, that led us into the science of astronomy and thence to other sciences, that gave us our understanding of our place in the cosmos, that held the stories of our mythologies, those skies are basically gone for the majority of us on Earth. This is within a generation; my parents had complete access to the darkest skies by walking out the doors of their houses into the farmyards of their childhood homes. In Selkirk, Manitoba, where I grew up in the 1960s and 70s, it was fairly easy to find the Big Dipper and Cassiopeia, but I can count my vivid memories of seeing the Milky Way on half the fingers of one hand.

I hardly know how to respond to this. I think dark skies are important. They remind us of our place in the cosmos. They instill a due sense of humility and wonder. They point to the origins of some our spiritual practices.

If you have the fortune to live under a dark sky, be grateful. You are one of the few. If you have the luxury of being able to escape your light-polluted home on a regular basis, take the time to do it. We don’t have to turn off the lights, but if enough of us seek dark skies often enough, maybe we will find it within ourselves to turn down the lights enough so that everyone can see the stars. It shouldn’t be a privilege.