Bright stars in the night sky are central to the joy of Christmas. Santa Claus and his reindeer glide to earth through a crystal-clear star-filled night.
Christmas trees are crowned with the Star of Bethlehem, the beacon in the sky that leads the three wise men to the birth place of Jesus.
Our Christmas stories need an unpolluted night sky where the sparkle of the heavens is clear and joyous. Unfortunately the sparkle of the heavens is disappearing.
We lived for six months in the centre of London a couple of years ago not far from the hustle and bustle around Marble Arch at the end of Oxford Street. Our apartment stood inside a secluded old garden planted thick with trees from around the globe. Nevertheless, artificial light from the city flooded our bedroom at night making deep sleep difficult. A bloke down the pub put it in context. You can see London from outer space, he quipped, but you can’t see outer space from London.
I remembered our time in London when I was in the middle of Parramatta late at night last week. Although everything was shut down thousands of switched-on lights kept the city aglow. Bright street lights meant I could see for hundreds of metres in every direction, except skywards.
As I exited Parramatta’s city centre I saw the ground spaces around the new apartments along the river front were also brightly lit, perhaps as a security measure, and I wondered whether it was possible to sleep in those stacked bedrooms without heavy drapes.
A study reported recently in the journal Science Advances shows we should be worried about all this night light and the loss of the ink-black sky. Artificial light has colonised the night especially in the world’s big cities. Where in western Sydney can you stare into a black sky and wonder at galaxies that stretch forever into infinity?
The study notes that the loss of darkness at night is affecting the vigour of life on our planet. Living things, like us, that need darkness to sleep suffer when the natural day-night cycle loses its intensity. Then, those organisms that are nocturnal – apparently 30% of the world’s vertebrates and more than 60% of its invertebrates – suffer because the loss of darkness curtails what they can do during their waking hours. Many animals, birds and insects need the protection of darkness to feed and mate.
Economic growth and urbanisation are the main causes of night-time light pollution so it’s not surprising we are losing the opportunity to gaze into an ink-black sky. An intriguing finding of the study is the effect of LED lights. These not only make outside lighting cheaper, hence more prolific, they emit white-toned light different to the softer yellowish light from the old sodium bulbs. The white tones make the atmosphere glow brighter.
I read that half of the children in England have never laid eyes on the Milky Way. I wonder how many children in western Sydney have never marvelled at the endless clouds of stars up above.
Can you point to the heavens where you live and show your children and grandchildren that our planet sits on the edge of a galaxy made up of over 100 billion stars? Can you lie outside in the dark of night and tell them there is one star in the Milky Way for each person who has ever lived – and that beyond the Milky Way there are two trillion more galaxies?
I’ve never met a person not enthralled by the wonder of it all.
Some say a dark night sky makes them feel confident, not scared, about the night, and a very small part of something marvellous. We need to ensure our children and grandchildren can see the universe that is around them. Sadly, Sydney’s planners and developers seem unconcerned about the damage caused by artificial light at night.
But, switch by switch, we need to make our nights dark again.
- Phillip O’Neill is director of the Centre for Western Sydney at Western Sydney University.