When in astronomical history would you have liked to have lived?
Imagine looking up at the night sky on a clear, cloudless night and seeing the awesome majesty of the night sky spread out above your head from horizon to horizon. A literal countless number of tiny colourful, twinkling dots of light that slowly move from east to west and gradually change as the seasons progress.
Now imagine looking up at the night sky on a clear, cloudless night and seeing a dull orange haze and maybe, if you’re very lucky, a few hundred tiny colourful, twinkling dots of light that slowly move from east to west and gradually change as the seasons progress.
Which view would you prefer?
Most people would probably pick the first. Modern light pollution has reduced the number of stars that we can see to only the very brightest, obliterated the Milky Way and outshone the Andromeda Galaxy. The night sky that our ancestors saw was a very different sky to the one that most of us see today.
I had the good fortune, several years ago, to go and visit Uluru. Whilst there, at midnight, in the middle of central Australia, with the nearest light bulb somewhere close to 25km away, I saw the night sky as it was meant to be seen - the Milky Way, the Large and Small Magellanic Clouds; there were that many stars, it was difficult to pick out the constellations I knew. I was blown away by the sheer magnitude of what I was seeing. As my eyes dark adapted, more and more stars came into view, until the entire sky seemed to be filled with lights. It was magical.
This is the view that I would dearly love to have above my head every night. Imagine having that illuminated sky visible night after night.
You don’t have to go that far back into history to find the skies over the UK that dark - gas and electric street lighting and house lights are relatively recent inventions. Go back only a couple of hundred years, and the towns and cities of the UK would have been relatively dark at night, and you would only have to travel a short distance to find a site with no light pollution.
Go back a bit further, and you would only have a few lanterns and candles here and there, further still, and you would have to carry your own lantern or torch around in order to be able to find your way around at night.
Our ancestors had the night sky, we have light pollution.
However, today, we understand what stars are, how far away they are, and what our place in our galaxy is. We have telescopes in almost every imaginable wavelength that can probe the sky from microwaves to gamma rays enabling us to build a picture of what the universe is made of, how large it is and how it is evolving. Our ancestors had telescopes that operated only in visible light, were limited in the magnifying power, and before the telescope, only their naked eyes to observe the stars and planets with. They didn’t know what the stars were, how far away they were, what they were made of, or even that the universe was not just what was contained within our galaxy.
These discoveries were made in the last hundred years, the exact same hundred years that saw the night sky almost washed out by light pollution.
The tragedy of the modern era in astronomy is that, whilst we understand the sky in ways that our ancestors could never have dreamed of, we cannot see it in the way that they did.
Greater understanding of a thing does not detract from its intrinsic beauty. To know that a star is a truly massive sphere of plasma, held together by gravity and powered by nuclear fission in its core in no way reduces the beauty of seeing that tiny, twinkling dot of red, blue or white in the sky, surrounded by its celestial cousins.
So we have a trade off, knowing this about what the sky actually holds, against being able to see it properly.
Those who looked into the sky 500, 1000, 2000 or 10,000 years ago only really knew that there was something up there, not what it was, how far away it was or even what it was made from or how it got there. Myths and stories were invented to explain it, tales of heroes, gods, mythic beasts and canopies with holes in were spun to explain the fixed nature of the heavens, with the planets, the ‘wanderers’, being especially epic creatures, gods or heroes who could move amongst the other celestial inhabitants.
Today, these stories still exist as myth and legend - Hercules, Andromeda, Perseus and Pegasus, the names of the planets as classic gods, all reflect their mythic status from the past. The fact that we know the planets move according to Kepler’s laws of planetary motion and are held in place by gravity adds to the beauty of the mechanics of the system.
So, would you rather live in an era where the stars were pinpricks in the curtain of night, allowing the light of heaven to shine through onto the Earth, being able to see the entire night sky in all its glory; or would you rather live in an era where the stars, planets, galaxies and universe are at least partially understood, but with the glory of the night sky severely diminished?
Personally, I would rather live today and help the Campaign For Dark Skies, in order to keep the skies as free from light pollution as possible than in the past, no matter how alluring the thought of a truly light pollution free sky is. I would rather see fewer and know more (and fight for the ability to see more) than see more and know less.