Happy Dark Sky Week!
The next time it’s a clear night, go outside, look up. What do you see? Is the sky really black? Or is it orange? Dark blue? How many stars do you see? I’m guessing you can count them.
Have you ever wondered why we call our galaxy the Milky Way? It comes from the ancient Greeks who called it galaxies kuklos, meaning “the milky circle.” It was then translated into Latin by the Romans who called it via lactea, meaning “the milky road.” They believed that the stars that stretched across the sky looked like flowing milk. Is that what the night sky looks like to you? I don’t imagine that’s the case. Not unless you live in a remote location. And most of us live close to some nearby city. If you think you don’t, here’s an experiment: grab a camera, place it on a tripod, and set it to 20 seconds. Then take a look. I bet the sky has an orange hue to it.
I took this image on August 17, 2012, near the Blue Mountain area of Ontario. It is considered a somewhat “dark sky” location. I am facing roughly south. Can you guess what that orange glow is? That’s Toronto — 170 kilometres away.
City lights, among other things, are a scourge on our planet. Their light doesn’t shine down, where we seem to need it, but rather down, outwards and upwards.
Astronomers aren’t the only ones who crave the dark: our bodies do as well. We are looking at hundreds of thousands of years of human evolution where light occurred in the day and the night was actually dark. It is where we received our rest, and our bodies used that time to grow and heal. The constant light disrupts this circadian rhythm. What will the long-term consequences be?
But perhaps it is in wildlife where the adverse effects of light pollution is most readily visible. Birds that migrate at night collide with constantly lit office towers; songbirds sing at unusual hours; breeding is affected. The haze of towns have been known to confuse newly hatched turtles who would normally head out to the brighter sea; instead they turn toward city lights.
What is probably most frustrating is that rectifying this light pollution issue is an easy one. Cities only need to put in lighting bylaws requiring office towers to turn off lights. Towns and cities can enforce full cut-off lighting where the light is directed downwards to where it is needed. I am proud to live in a town with a lighting bylaw.
This is the Milky Way. THIS is what our night sky should look like. Let’s bring back the night.
WHAT YOU CAN DO TO BRING BACK THE NIGHT
1. Only turn on the lights you need; once you leave a room, turn off the light.
2. Put lights on timers
3. Use dimmer switches
4. Buy full cut-off lighting
5. Write a letter to your city/town representative asking that they consider a lighting bylaw or full cut-off light fixtures.
FOR MORE ON LIGHT POLLUTION AND HOW IT AFFECTS YOU AND WHAT YOU CAN DO ABOUT IT, VISIT THE INTERNATIONAL DARK SKY ASSOCIATION (IDA).