Highlands Astronomical Society, based in the City of Inverness, is one of the most northerly mainland U.K. clubs and was formed in 1994 by a handful of enthusiasts. Since that time Society membership has steadily increased to over 60 and meets on a monthly basis year round. In addition to our regular meetings, we hold special events, exhibitions and observing sessions throughout the year. Events to which the general public are invited are usually well attended by a broad spectrum of ages. Society members write a regular monthly astronomy article for a local newspaper, we have a successful web site, www.spacegazer.com, and our own observatory, situated to the east of Inverness.

  The Highlands of Scotland are one of the few areas of the country where truly dark skies can still be found but over the last few years the pristine skies have come under increasing threat due to above average population growth. This threat has been made even more apparent by the fact that even the smaller towns along the Moray Firth can now be clearly seen from space as a result of light spillage.

INQUIRY TERMS OF REFERENCE:

1.  What has been the impact of light pollution on U.K. astronomy?

  (a)  The minimal attempts to control light pollution thus far have, in the main, been ineffective in preventing an ever growing level of light pollution in all areas of the country, especially in towns and cities where only the brightest stars remain visible through the unearthly background glow caused by inefficient, unnecessary or excess lighting.

  (b)  From an unpolluted site it should be possible to see around 2,500 stars in a dark moonless sky. This figure can drop to as low as 25 in the worst urban areas and even `rural' areas like Inverness can suffer a drop of up to 90%, depending on which part of the city one is viewing from. From built up areas the Milky Way has disappeared during the last few years, as have many of the deep sky objects, which used to be visible to the naked eye. Current estimates suggest that over 90% of Europeans will be unable to see the Milky Way due to light pollution.

  (c)  Astronomy is one of the few areas of investigative science where amateurs can, and do, make important contributions and discoveries. Amateur input is actively encouraged by professionals who are constrained by budgets and limited observing time on the relatively small number of research grade instruments available to them. The relentless rise in light pollution has resulted in amateurs having to travel increasing distances to find dark sky sites to observe from, or having to invest considerable sums in larger instruments or electronic aids in order to combat declining visibility at their home location. There are many instances of both professional and amateur casualties due to light pollution, for example Edinburgh and the amateur club on the South Downs who had to open a planetarium instead of an observatory. Despite the less than perfect climate, the U.K. used to be at the forefront of astronomical investigation and discovery but we now play a role, if lucky, as minor partners.

2.  Are current planning guidelines strong enough to protect against light pollution?

  (a)  Planning guidelines are voluntary, not mandatory, and are frequently ignored for a variety of reasons such as cost of fittings, "decorative" use and inappropriate highlighting   of public buildings or monuments. When guidelines are followed, eg. the use of full cut-off fittings for highway illumination, the results can be very good with no light spill above the horizontal. The fittings provide an added bonus of increased safety due to the more even illumination and lack of the stark delineation between light and shadow.

  (b)  City Planners ignore the Good Lighting guides when addressing their own particular areas, evidenced by the wasteful `decorative' lighting used in most city centres, in particular the many remaining globe lights which emit light in every direction. These could quite easily be capped. Lighting of official buildings and monuments could be accomplished by illumination from the top down instead of searchlights based at ground level. Sports centres and golf ranges are also examples of excessive use of light and are visible from miles away.

3.  Are planning guidelines being applied and enforced effectively?

  (a)  We know of no local case where enforcement has taken place to correct bad lighting. Local authorities can, in fact, be the worst culprits, demonstrating an erratic approach to even the installation of highway lighting by following up a model installation of full cut-off lights with one of old fashioned, light spilling fittings. Short-term budgetary considerations tend to lead to the purchase of cheaper, inefficient luminaries. Local authorities are unwilling, for political reasons, to take a long term view of the savings in power consumption resulting from the use of the lower wattages required when light is directed where it is needed and not up to 30% into the sky. There are considerable environmental impacts from the profligate use of light, ranging from increased use of valuable fossil fuels to generate the power necessary, to adverse effects on the circadian rhythms of both wildlife and humans. Most species require a dark/light cycle to function at optimum levels and even minimal light intrusion during the "dark" cycle can have disruptive effects.

  (b)  Light, unlike noise, is not legally classified as a pollutant and was deliberately excluded from a list debated by Parliament in the early 1990s, despite causing more a more widespread problem than noise. As a direct consequence of the lack of enforceable controls, light trespass is becoming endemic. Of particular concern to the amateur astronomer is the proliferation of so called `security lights' which, when positioned badly, can illuminate all properties adjacent to the one fitted with the light. This is another case of bad design as these mass marketed lights are fitted with unnecessarily high wattage bulbs of 500 watts and most of them cannot be fitted in such a manner as to ensure a downward pointing beam. Research has shown that the area lit by these fittings is so bright as to make anything in the shadows invisible, hence aiding any clandestine activity in the gloom. Again, short of individual legal actions to recover our right to darkness, nothing exists in statute to protect our pastime from the depredations of bad design and excess light.

4.  Is light measurable in such a way as to make legally enforceable regulatory controls feasible?

  (a)  Most definitely. The ability to measure light output, subject illumination and sky transparency has been available for some considerable time. The Institute of Lighting Engineers can provide recommended illumination values for various types of lighting, eg Roads, recreational, etc. It is therefore a simple matter to calculate how much wattage is required to adequately illuminate a specific area, matched with an efficient light fitting, which emits light in the desired direction. Light levels can be quite simply read off a meter. If in excess of a recommended maximum, the wattage can be reduced.

  (b)  Stray light, ie that which is emitted in a direction other than intended to illuminate the subject, can also be measured by meter and should be kept as close to zero as possible. Skyglow, the visible result of light pollution or overspill, can also be fairly easily measured using several methods. For example, comparative measures between the zenith (overhead) and the horizon using a densitometer would indicate degrees of darkness and hence levels of pollution.

5.  Are further controls on the design of lighting necessary

  (a)  Light fittings for use in public places should be of the full cut-off design and use a wattage, which is sufficient to illuminate the subject without unnecessary glare. This would have several benefits; less power consumption, no upwardly emitted light, a more natural environment in which the human eye could perform at its best and better safety as detail in the shadows would be more easily distinguished.

  (b)  Local Authorities must lead by example. Public buildings and monuments should be more sympathetically lit and not floodlit from ground level upwards. Industrial estates, which are unused at night, do not need megawatts of illumination for security and shops do not need to have windows lit all night. Better designs of luminaries are available now and should be used exclusively for new developments, sports centres, golf ranges, car parks and advertising. These requirements can easily be brought into the realms of planning controls now, as could the use of "security" lighting. T.V. antennae and satellite dishes are within the remit of planning controls, so why not nuisance lighting? Unnecessary lighting should be switched off at 2300.

  (c)  Local Authorities and highway departments should be required to replace old light fittings with low-pressure sodium lamps in full cut-off fittings when renewal becomes due. Extraneous light from these lamps is easier to filter out for the amateur astronomer than the more common high-pressure sodium lamps.

  Since the dawn of time, humans have lifted their gaze to the sky to stare in wonder or curiosity. Today is no different and many thousands of people, who would not necessarily categorise themselves as astronomers, still derive much enjoyment from simply looking. There has been a tremendous increase in interest over the last few years due to press and television coverage of space related items and, in particular, the stunning images from the Hubble Space Telescope and the giant ground based telescopes in Hawaii and South America. Sales of telescopes and binoculars are increasing exponentially with new retail outlets appearing monthly. Astronomical clubs and societies are attracting more and more interested people to their open events and star parties, even in less than ideal observing conditions.

  Visibility of the sky is not a privilege, it is our right. It is one of the few remaining areas of outstanding natural beauty and scientific interest, which is still available free of charge to all and which must therefore be protected for succeeding generations. The damage caused by light pollution is reversible, given a little concerted effort, but will take some time. All the more reason to take the first steps now and follow the examples set by countries like Italy, Germany, several States in the USA, Canada and, most dramatically, Czechoslovakia, in enacting legislation to clear up our night sky and restore darkness for the enjoyment and education of many.

24 April 2003