Lightness and Darkness

A few days ago I was musing in the twilight between sleep and awake and later wrote it up, thinking I might use it to fill the blog for a non-moving day. In the end I did not get around to it but this morning my attention was drawn by one of the dreaded algorithms (which think they know my psyche better than I do!) to this Guardian article "The night sky is getting 10% brighter every year. We're forgetting what darkness feels like".

So here is my musing:

I first awoke this morning just after five, needing to go to the bathroom. It struck me just how much ambient light there was. Like almost every marina we have stayed at, short and long term, there are plenty of outdoor lights that illuminate every part of the marina. No doubt the reason is a belief that this adds to the security of boats and people at times when there is no member of staff on duty. But it is a non-trivial cost, in terms of the electricity supply that ends up as part of mooring fees, as well as environmental. We tend to forget, or at least turn our forgettery towards, the impact of artificial light on the environment.

If you live in a marina, or more likely one of our dense urban areas, you will perhaps take night time lighting for granted, a necessary component of modern living. Only occasionally does a local highway authority consciously decide to reduce or eliminate night time street lights. We are today unsurprised by satellite images of the planet earth that show the night time light emission. We draw the obvious conclusion that such displays are a good surrogate for population statistics - the more light, the denser the population.

On the other hand, when we moor in a rural location, and if we are lucky, we will experience night time 'as it was made' with only the occasional unclouded full moon to disturb the sense of isolation. At the same time, our appreciation of night time sounds may also be enhanced (unless, like me, you miss this without hearing aids!) Growing up in mid twentieth century England I suspect that I, like almost everyone doing so in towns and cities, will have unconsciously divided the day in to night and day, with one part being when everything happened and the other where the whole world went to sleep. Only later did the twenty four hour society eat away at such preconceptions, even if they still lurk in the deep recesses of the psyche only to emerge when they ought not.

Standing in the bow of a boat on a rural mooring usually brings to our attention that nights are not simply silent, but sometimes different. We soon notice the sound of traffic on a trunk road that is at least two miles away. On the other hand, if we are lucky we also hear natural sounds that mean that we are never in complete silence - or total darkness.

If a random sample of urban dwellers was asked why we have night time outdoor lighting, whether street lamps, industrial floodlighting or whatever, I suspect that the great majority will look quizzical and just shrug their shoulders at what is an assumed fact of life. It is obvious that the world is a better, safer, more productive place with such lighting - and light pollution. Astronomers - whether amateur or professional - will be all too aware that even the smallest light pollution diminishes our ability to observe phenomena such as the Milky Way with any clarity, let alone more distant worlds.

I wondered whether there has been much objective research to estimate what value such lighting really delivers. Does it actually return a positive benefit on the cost? Are the lights turned on just because there is an in-built assumption - if a marina does not provide it do its customers complain or feel under cared for?

Is it perhaps that we have collectively acquired a fear of darkness? Is it related to a sense of isolation, lack of contact with humans or even the world itself? Would a conscious experience of darkness make a positive contribution to our well being? Or does a fear of isolation generate a craving for otherwise unneeded illumination?