Conserve the Dark

We are very fortunate in Metchosin to have relatively dark night skies. People from around the CRD come here to take advantage of this increasingly rare situation (especially so close to an urban area). The Royal Astronomical Society of Canada’s star parties, hosted on the Metchosin Municipal grounds, have been very popular over the years as a way members of the public can have a chance to peek through a telescope at distant celestial objects.

One notable recent celestial event that many Metchosinites witnessed was The Great Conjunction of Jupiter and Saturn in December 2020, which was followed by the addition of Mercury to make it a triple conjunction on January 7. In March we will see the moon make conjunctions with Jupiter (March 9th), then Saturn (March 10), and finally Mars (March 19). On April 21-22 we will have the Lyrid meteor shower, an annual event that has been witnessed by humans for at least 2,700 years, produced when the Earth passes through the tail of the comet C/1861 G1 Thatcher.

Clear, dark skies are essential to good star gazing – a source of wonder and enjoyment for many. Darkness in general is essential to human health, as well as that for wildlife and ecosystems.

For humans, researchers have shown that darkness helps our creativity and mood. Too much artificial light at night, specifically during our “circadian trough” between midnight to 6am, over the long term is harmful to us, and is even considered a probable carcinogen. It can lead to higher incidences of diabetes, cardiovascular problems, depression, substance abuse, obesity, breast cancer and prostate cancer (melatonin production in the body is believed to help ward off these cancers, which is disrupted by artificial light at night).

As for nature, the impacts of light pollution were recently surveyed in a meta-analysis (a study that compiles the state-of-the-art in scientific knowledge on a subject) by the University of Exeter, which showed that activity patterns, breeding cycles, vulnerability to predators, and hormone levels are being affected across a broad range of species. The effects were found everywhere – among microbes, invertebrates, animals and plants. This manifests as reduced pollination by insects, insect deaths on lamps, and trees budding earlier in spring, to name just a few known ways that artificial light disrupts nature.

The ever-growing urban footprint of the CRD is rapidly reducing where dark night skies can be enjoyed in the region. This is not only a shame for people who are deprived of this fascinating experience, but it is a threat to our local flora and fauna. Light pollution is a growing problem, but fortunately one that we have easy solutions for. Limiting urban sprawl is one, for which Metchosin has done a great job thus far. Another is to limit the amount of light that is able to shine in directions it’s not needed. This means shades over lanterns intended for lighting roads, parking lots, and sidewalks, reducing light and energy wasted shining skyward. Some municipalities have bylaws requiring this. Limiting outdoor lighting in residential settings is also important, particularly for the localised effect it has on rural and urban wildlife. Turning off non-essential lights (or using motion sensors if security is your concern) goes a long way to doing your part to reduce the harmful effects of light pollution to both your neighbours and nature.

Like our parks, trails, forests and beaches, Metchosin’s dark night skies are a special part of our community’s natural capital. They allow us to step beyond our nighttime doorways and appreciate celestial phenomena that are timeless – and increasingly difficult to experience elsewhere.

To learn more about this subject, the TEDx talk Why We Need Darkness by Paul Bogard is very informative, and this brochure published by the Royal Astronomical Society of Canada has practical tips on reducing light pollution.

April 5 – 12 is International Dark Sky Week. Take some moments to enjoy our precious dark skies in these fine clear spring nights.

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