INTRODUCTION

  I am submitting this evidence as Chairman of The Croydon Astronomical Society on behalf of our current membership of about 90 people and on behalf of those in the local society that we aim to assist.

BACKGROUND

  The Society is a registered charity with the following objectives (taken from our constitution):

(a)  To encourage a popular interest in Astronomy and allied subjects for persons living in an area as defined in Rule 3.

(b)  To help and educate beginners, irrespective of their age, to acquire a knowledge of Astronomy and allied subjects.

(c)  To encourage observational and practical work within the power and means of the members.

  We meet these objectives through two main activities.

  First we provide fortnightly lectures by a mixture of professional and amateur astronomers which are open to both our Members and the general public these are not effected by light pollution except as it discourages people from becoming interested in Astronomy in the first place, this will de discussed further below.

The second activity is directed towards encouraging observation, we do this both through providing practical advice and assistance to members who wish to start observing and through the provision of our societies observatory that is at Kenley Aerodrome just on the edge of the "Green Belt". In addition to the use of the observatory by members we provide an invaluable resource for various educational and affinity groups. These range from the local Cubs, Scouts, Guides and Brownies, school groups—particularly those studying GCSE and A Level Sciences, Students from Astronomy Evening Classes, groups of local residents and Women's Institutes. As one of the very few facilities available to these groups in our visitors come from London, Surrey or North Sussex The observatory is also open to the Public on most clear Saturdays and has a steady stream of visitors mostly with children in tow. We have also used the facilities to show The Member for Croydon South Richard Ottoway MP views of one of the brighter comets.

THE SOCIETIES OBSERVATORY AT KENLEY AERODROME

  The observatory is built on a small piece of land that was donated to the society. Construction started in the early 1970's and took several years. Most of the effort went into constructing the telescope which at the time was "cutting edge" technology for an amateur telescope and is still one of the largest instruments open to the public. When the observatory was built the skies around Kenley were quite dark but while the immediate surroundings are still reasonably dark due to the lack of nearby buildings and the unlit road the darkness of the sky has suffered serious deterioration due to scattered light, the ubiquitous orange glow that now covers most of our towns and cities. We also have some local problems where excess light from poorly positioned or designed light sources produces significant pollution. Our worst "spot" sources are car park lighting on a public house at about ¼ mile from the observatory, School "security" floodlights at ½ mile and sports ground floodlighting at 0.8 mile though while bright this is helped by the fact that it is turned off at 10 pm.

  At present the light pollution levels to the North of the observatory which looks towards Croydon and London are high, the levels to the East and West are Moderate to High and to the South are moderate. An indication of the levels of "skyglow" at the site is the fact that despite the fact the nearest significant streetlights are ¼ mile away there is sufficient light from the sky to see to walk round the area safely after your eyes adapt to the darkness.

EDUCATION AND THE CROYDON ASTRONOMICAL SOCIETY

  Astronomy is an unusual science in that there is still a very close bond between the professional Astronomers and their Amateur counterparts, a significant number of amateurs still carry out observational research that is of used by their professional colleagues. One of the principal reasons for this is that there are comparatively few large telescopes available to professional astronomers due to their cost and these are dedicated to very specific programmes leaving no spare capacity for more general searches. Thus amateurs assistance is invaluable in following the light curves of variable stars, searching for objects that have had a sudden change of brightness such as nova and supernova as well as discovering comets though the British astronomers have not had much luck in this area. Amateurs are also involved in the hunt for "Near Earth Objects" and other asteroids.

  The society has encouraged a large number of people to become interested in Astronomy and while a few have gone on to become involved in the professional field a considerable number of others have either studied Astronomy at University and then moved onto other technological fields or have gone into other areas of science or technology and have thus contributed to Britain's prosperity. Our most successful ex member is Professor Paul Murdin who has recently taken a post at Cambridge University, we have also got two members who are working on the PPARC funded telescopes on La Palma.

THE EFFECT OF LIGHT POLLUTION ON THE SOCIETY

  The high levels of light pollution effects the Society in several ways. Some of our members who live close to local sources of light pollution find making observations very difficult and this has resulted in a number of our members moving permanently to areas with darker skies either both within the UK and abroad.

  Light Pollution also has a more insidious effect on the potential membership as very few of them are ever able to see the true majesty of the night sky from a dark site. Even when they go abroad on holiday a lot of resorts are so light polluted that their view is little of any better than at home. There is also a secondary effect that few people realise that it takes the human eye some 20 to 30 minutes to become fully sensitised to low light levels, as a result they do not stay out long enough to see what is visible or indeed to appreciate the high levels of light pollution that exist. When we are explaining aspects of astronomy to some of our younger visitors it is obvious that a large number of them have never seen the Milky Way due to light pollution.

  We believe that the high levels of pollution have resulted in a decline in interest in people wishing to observe the sky directly though to some extent this is counteracted by the flow of spectacular Astronomical Images that are available through both the Internet and Magazines. Practical observing also builds skills in a number of other areas such as operating scientific equipment, computing and mathematics.

LOCAL LIGHT POLLUTION—CROYDON SKYLINE

  Croydon Skyline is a project jointly funded by lottery grants and local businesses designed to "enhance" the night time environment of Croydon by floodlighting various buildings. When this project was announced the society was extremely concerned as we were aware that poorly implemented schemes would have a significant effect on the quality of the local night sky.

  The society decided to get directly involved with the project by having representation on the board but while we had significant impact on the guidelines to ensure that small downward facing lights should be used to light the faces of the buildings this proved too expensive for the members of the scheme and a significant number of the schemes used upward pointing lights from ground level which have resulted in a large proportion of the light missing the buildings entirely and just adding to the already high levels of light pollution above Croydon. The poor design of the lighting in the Croydon Skyline Project has been reviewed in page 21 of the March/April 2002 Edition of "The Lighting Journal" which is the journal of the Institution of Lighting Engineers . The large amount of overspill has resulted in sufficient light directed upwards to provide an illumination hotspot on the clouds up to several thousand feet in height. As a result the project is locally known as "Croydon Lighthouse" as one of the more complimentary names.

  Without going into the specifics of all the poor installations two are notable, The Nestlé Building this suffered considerable overspill but representations by one of our members eventually resulted in Nestlé spending a significant amount of additional money to modify the scheme that resulted in a reduction in the light pollution. The other building that is worth mentioning is The Immigration Departments "Lunar House" building, the lighting scheme for this uses totally inappropriate lights and despite some attempts to improve the scheme with baffles a large proportion of the light still misses the building. Even if upwards directed light all hits the building a significant amount of it will bounce off and head skyward.

LOCAL LIGHT POLLUTION—OTHER SOURCES

  There are a wide variety of sources that combine resulting in the high levels of pollution and of course wasted energy that are visible ever time we walk out at night. It is impossible to give a complete list here but in general any light source that emits light above the Horizontal or is too bright for the requirement contributes to light pollution.

  Some examples are:

  Light trespass from streetlights into adjacent land—generally due to the use of lights that do not use "full cut off" luminaries.

  Domestic "security lights" these are commonly shown on the packaging as being installed with the beam horizontal which results in light trespass onto other properties as well as glare that allows intruders to hide.

  Security and display lighting on commercial property and schools, a lot of this is poorly designed and installed resulting in Light Trespass, Pollution and Glare.

  Sports ground lighting, due to their high power and a design that shines light outside the desired area these are a major source of pollution—there are three sites in the local area where the pollution is clearly visible.

OBSERVATIONS OF LIGHT POLLUTION

  While light pollution can be observed from ground level it is perhaps most obvious from above, anyone who has flown over the UK on a cloudless night can easily observe how much of the light is directed upwards wasting energy and causing pollution. Even more dramatic pictures can be seen from space, the web page at http://antwrp.gsfc.nasa.gov/apod/ap030411.html has a copy of a photograph of London taken from around 230 miles altitude using a standard digital camera. The light pollution sources are quite obvious and it is easy to pick out both the pollution from the centre of Croydon and the retail parks along the Croydon stretch of the A23.

CURRENT CONTROLS

  The only controls that appear to be effective are those applicable to "Sky-beams" and other upward aimed searchlights and laser beams. Following a court judgement these have been classified as advertising and as such require planning permission. This does not appear to stop them being used for various one off events though, by the time the source has been located and the appropriate council have been mobilised they have normally gone.

  The article referenced above on Croydon Skyline describes some of the problems with implementation even if a scheme is specified to meet certain constraints what is installed is often non-compliant with the original standards and it appears that there is little motivation to sort the resulting problems out.

  The British Standard for Street lighting requires that street lights in the vicinity of Astronomical Observatories should be designed so that they preserve the dark sky but I have no evidence that this requirement has been followed by any of the relevant Highway Authorities in the Area.

MEASUREMENT

  While the society is not an expert on the measurement of light pollution there is a web site describing the work of Professor Cinzano, University of Padova, Italy at http://debora.pd.astro.it/cinzano/en/index.html. He has used measurements from an American Satellite to map the levels of light pollution across the world. There are some very detailed maps showing how bad the situation is in the UK and how the amount of light pollution in the UK is much higher than some of our European Neighbours. One of the maps shows how the light pollution from England merges with that from France so even the centre of the Straits of Dover is not free from pollution !

  One also needs to consider that the light heading out to space requires particles or large molecules in the atmosphere to scatter off before it becomes a problem, while some of the particles are natural a large percentage are the result of air pollution from man's activities.

CONCLUSION

  I hope you find the information in this submission of use to your enquiry. Please do not hesitate to contact me if I can be of further assistance.

16 April 2003