Dark Skies -Bright Stars, PLEASE!

By: John Hlynialuk

Amateur stargazers, cottagers and nocturnal animals are really lucky to be living in Bruce and Grey counties. Stargazers have dark skies and bright stars to observe. Cottagers (away from overly-lit urban areas) have dark skies and a beautiful swath of summer Milky Way overhead when the family is out cooking weenies over a campfire. Nocturnal animals that live near or in the Bruce Peninsula Biosphere Reserve have nighttime darkness to which they have adapted over the millennia -no pesky streetlights making them well-lit targets for predators.

The common theme here is, of course, dark skies and a natural environment. Many places like the Bruce Peninsula Fathom Five National Park and the Bluewater Outdoor Education Centre are still mostly pristine environments and from a stargazing perspective, protected from unnecessary nighttime lighting, be it incandescent, florescent, or the most recent abomination, LEDs.

Keeping a dark nighttime environment is crucial for human health. Just google “Dark skies human health” for dozens of medical studies that support this contention. Fortunately, in the Bruce/Grey area of Ontario, nighttime over-illumination is only a problem in a few localities. Furthermore, efforts to preserve the dark nighttime environment locally have borne fruit. There are 17 Dark Sky Preserves in Canada, and four of them are within a 160 km radius of Wiarton. The four include Bruce Peninsula National Park near Tobermory, the Bluewater Outdoor Education Centre near Wiarton, Gordon’s Park on Manitoulin Island, and Torrence Barrens near Gravenhurst. Yes, locally we are optimistic about controlling light pollution, but the planet-wide scene is decidedly much the opposite.

Not to mince words, overall, we are losing the battle to control nighttime illumination. You just have to look at an image of the Earth at night from space to see how bright it is at night. Satellite cameras detect the totally wasted light sent upwards. Much light reflects back down from dust particles and water vapour and brightens the sky generally. The effect is visible even in rural areas as the visibility of faint objects is reduced. Even from 100’s of kilometres away, the light domes over our cities cast an orange glow into the sky. Anywhere near or within a large city, the glare from overhead lights is extreme, allowing only light from the Moon and bright planets to get through. Fainter objects are totally invisible.

[Click on image below to download a copy]

F3.large
Image from study published in Science Advance magazine.


A study in 2016 authored by Fabio Falchi of the Light Pollution Science and Technology Institute in Italy and Chris Elvidge of the US National Oceanic and Atmospheric Administration (along with other international scientists) has found that in the USA, for ex., 80% of the population cannot see the Milky Way from where they live. The percentage is the same in urban Canadian areas like those along the Windsor to Montreal corridor. The darkest skies on our planet are of course, in areas like the Canada northland and in countries like Madagascar, the Central African Republic and Greenland, where everyone can see the Milky Way by just stepping outside.
[The original paper is available here:
http://advances.sciencemag.org/content/2/6/e1600377 ]

I am lucky to be able to see the Milky Way from my back yard because my house blocks the city lights to the north but there are sickly yellow-orange glows along parts of the southern and eastern horizon. Of course, like other large towns and cities, no Milky Way is visible from downtown Owen Sound. The situation locally has gotten worse in the last few years because the city recently replaced the majority of their streetlights with LEDs. These are certainly more economical and do have proper shielding to prevent upward light spill, but the overall level of lighting has increased approximately 30%, so the total light reflected from the ground upwards (especially in winter) has increased by a large fraction. Many people have commented to me that they find the lights at night overly bright. I agree and have the measurements to prove it.

On Saturday afternoon, May 27, there is an opportunity to visit a Dark Sky Preserve during the Open House at the Bluewater Outdoor Education Centre. The Bluewater Education Foundation and Ducks Unlimited Canada are co-sponsoring this event and it is open to everyone. You are welcome to come to the Outdoor Ed Centre (maps on the BAS website given below) and enjoy the wagon rides, birding, hikes, and fun kid activities like critter-dippin’ and face painting. Events start at 1 pm and will include solar observing with (safely-filtered) telescopes from the Fox Observatory. Everyone is welcome and after the Sun goes down, the observatory will be open for some dark sky viewing. Come and see what a Dark Sky Preserve is all about.

Check www.bluewaterastronomy.com for more information.