The Well Balanced Universe


Bring back the stars

By Edmund Wood

Many books have been published about the “Wonders of the Natural World”, with pictures of the Himalayas, the Grand Canyon, Antarctic glaciers, and such like; but strangely all these popular volumes fail to include the most amazing and awe-inspiring of all our natural phenomena – the sky at night, as seen from a dark site.

Sadly, fewer and fewer people ever witness this wonder in all its true glory, even though it is potentially available to every able-sighted person, without any travelling expense whatsoever. Our night sky is blighted. The most beautiful vista in all nature is ruined by streetlamps, security lights and other nighttime illumination.

Throughout the whole of history up to less than a century ago, people could look up from anywhere on a clear, moonless night and see thousands of stars glittering in a black sky, in all directions down to their horizon. They could also see the faint, cloud-like band of the Milky Way dividing the sky into two segments. Every few years, a comet, with glowing, fuzzy head and spreading tail, would be clearly visible to all, adding to the wonder as it slowly travelled across the constellations. On regular dates each year, showers of meteors, also known as shooting stars, could be witnessed from town gardens or balconies, sometimes reaching rates of over a hundred per hour.

These days, such sights are observed by fewer and fewer people – either those who are lucky enough to live in a dark location, or else dedicated amateur astronomers who purposely travel to such a place for a particular nighttime viewing. The greatest shame about this state of affairs is that it is not necessary even if it is accepted that we need such modern conveniences as outdoor lighting.

What is the purpose of streetlamps? Their function is not to light up the sky, nor is it to inhibit people's nighttime vision by shining in their eyes, nor is it to illuminate nearby gardens and houses; they are there to light up the street. Sadly, they generally achieve all four of these effects. If streetlamps were properly designed by incorporating appropriate shielding around the top and sides of the bulb, they would fulfil their purpose without causing light pollution.

The same is true for all other kinds of nighttime illumination. How many people have gone to visit someone after dark and been shocked out of their wits by a blinding, automatic light suddenly flashing into their eyes as they approached the house door? This is about as friendly a reception as being screamed at.

Is the purpose of these lights to shock and annoy every visitor (and the neighbours)? Because that is certainly what they do. Again, such an effect is totally unnecessary, because it is so simple to provide proper shielding when the device is designed or installed, so that its light shines only on the ground.

Floodlights are some of the worst offenders. Their function is to illuminate a sports pitch, a building site, a railway goods yard, or some other large area. It is intrinsically straightforward to ensure that this is what they do and nothing more. No light should be directed outside the area in question in any direction. If it is, this is an offence against the public, and there should be a law against it.

The lighting of monuments and public buildings is becoming more and more common. Very often this involves a bright spotlight on the ground shining upwards at an angle. Consequently, most of the rays end up heading into the sky. It is much better in these instances to have a number of smaller, shielded lights strategically placed on the building or monument itself pointing downwards and inwards, so that all their light shines on the target in question. This also creates a much more pleasing effect.

One further factor to be considered regarding the appropriate design and use of lighting is that significant amounts of energy and money can be saved. If all the light from a bulb is properly directed with the aid of reflectors inside shielding, then only about one third of the wattage and expenditure is needed for the desired lighting effect in many situations.

Every member of the public can play their part in regaining the wonders of the night sky for their own benefit and that of their children by ensuring that they themselves cause no unnecessary pollution, by lobbying their local council and member of parliament on the issue, by informing friends and neighbours, and by joining the Campaign for Dark Skies at:

Copyright © March 2007 Edmund F Wood

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