Si è svolto a Lucerna – Svizzera il secondo simposio Europeo sulla protezione del cielo notturno.
Gli italiani sono stati rappresentati dal prof. Pierantonio Cinzano, ma comunque le nostre attivià anno interessato tutto il convegno in quanto diversi relatori hanno parlato della legge Lombardia 17/00 presa come esempio da imitare.
Per qualsiasi informazione: http://ens.ch/ens/sternwarte/lichtverschmutzung/ds2002/index.html
Si allegano gli abstract del convegno:
Abstracts
2 nd European Symposium on the Protection of the Night Sky
Under the Patronage of the Swiss National Commission for UNESCO
7-8 September 2002, Luzern, Switzerland
Talks
UK Campaign for Dark Skies update
Dr. Christopher Baddiley, 1 Kingshill Close, WR14 2BP, Malvern, Worcs. UK,
cj.baddiley@physics.org
The Campaign for Dark Skies has made significant progress in influencing the UK lighting industry to market well directed lighting designs, and has persuaded a number of District Councils to include external lighting restrictions and good practice in their planning regulations. We have also made progress in a number of other areas, and have had some specific local successes. This presentation is an update on these activities.
Artificial light and nocturnal bird migration
Prof. Dr. Bruno Bruderer, Swiss Ornithological Institute, Sempach, Switzerland,
bruno.bruderer@vogelwarte.ch
The majority of migrating birds, particularly small long-distance migrants using flapping flight prefer night-time for their extended journeys over thousands of kilometres. Milliards of birds fly each autumn from Europe to Africa and back in spring. Generally, in temperate regions, the majority of birds fly within the lowest 1000 m, migration being most intense in the first half of the night.
Birds depend very much on the sense of vision. Nocturnal migrants use the stars for orientation together with references on the ground, as long as visual flight rules are applicable; the magnetic field is an important back-up system, particularly in cloudy conditions.
The increasing anthropogenic light emission from the ground disturbs nocturnal migrants mainly in two manners: 1) In bad visibility conditions (mist, fog, drizzle), nocturnal migrants are attracted by light, such as light houses or “light domes” above towns; 2) Birds show shock reactions when hit by a strong light beam, such as light beams used increasingly for advertising purpose.
Light pollution and stellar visibility in Europe based on satellite measurements
Pierantonio Cinzano, University of Padova, Padova, Italy and Light pollution Science and
Technology Institute (ISTIL), Thiene, Italy, cinzano@pd.astro.it
We present the situation of light pollution, artificial night sky brightness and stellar visibility in Europe as obtained by the global monitoring carried on by our research group and based on DMSP satellite data. We also shortly discuss some of the necessary measures for an effective limitation of artificial night sky brightness based on the physics of the light pollution propagation and on an evaluation of the pollution by some road lighting installations obtained with the software RoadPollution.
Light pollutions broad spectrum
Dr. David Crawford, Director, International Dark-Sky Association, 3225 N First Ave, 85719
Tucson AZ, U.S.A., crawford@darksky.org
Light pollution exists almost everywhere and is growing rapidly. Fortunately, there are solutions. The main problem is a lack of awareness, followed by the inertia of doing something. However, progress is being made.
The beauty of the night sky is a wonderful thing. In addition, decreasing light pollution helps greatly to improve the quality of night lighting for everyone. With good lighting, we improve visibility, safety, and security, minimize energy waste, and have a more comfortable nighttime environment. In addition, all living things have evolved with a day-to-night cycle, brightness and darkness (circadian rhythm). This rhythm is part of our nature, and we need it. The International Dark-Sky Association has a great deal of helpful information about the problems and the solutions on its Web site, www.darksky.org.
Ecological consequences of light pollution on nocturnal insects
Prof. Dr. Gerhard Eisenbeis, Department of Biology, Institute of Zoology, Johannes
Gutenberg-University of Mainz, 55099 Mainz, Germany, geisenbe@mail.uni-mainz.de
Nocturnal insects are extremely sensitive to outdoor lighting because they have evolved special adaptations of photoreception. They are often attracted to endless turns in the light sphere of lamps, but there are also some other exogenous and endogenous factors that control their behavior. For the evaluation of catch data sometimes it is very important to take into account the background illumination, which affects the ‘zone of attraction’ rsp. the ‘region of influencé of lamps significantly. Two models are presented to show the flight behaviour of insects at dark sky and at moon sky. The death struggle of insects around light sources can be described by special effects, e.g. ‘captivation or fixation effect’, ‘crash-barrier effect’ or ‘vacuum cleaner effect’. In many cases insects become disorientated by these effects and are no longer able to perform their basic functions of nutrition and reproduction. Some results from a study within a rural landscape of Germany will be presented,showing the impact of different street lamp types on insects during a full summer season. These differences were quantified as capture ratios regarding both the bulk of insect orders or special orders alone. Besides light quality the habitat characteristics revealed to be important in this context, too. Additionally the influence of full and new moon, and of the evening temperature on the nocturnal activity of insects will be shown. All these facts give reason to question whether outdoor lighting is a serious threat of insects or not? Based on results from literature an attempt is made to calculate the dimension of insect mortality regarding a street lamp pool of a larger city up to the whole area level of Germany. Thereafter some aspects are considered how species and populations with different life strategies may be influenced by lighting. Finally, examples of energy savings from converting older street lamp systems into modern systems will be shown, especially the change away from high-pressure mercury lamps, which may reduce energy costs and CO2 emissions significantly. The modernization of public lighting is beneficial both for township budgets and for the agenda of nature conservation, especially of insects.
Precise Evaluation of Upward Flux from Outdoor Lighting Installations (applied
in the case of roadway lighting).
Mr. M. Justin, Marc Gillet (Schréder Group), Prof. P. Rombauts (University of Brussels -VUB),
R-Tech (Schréder Group), rue de Mons, 3B, B-4000 Liège, Belgium,
Marc.Gillet@RTECH.BE
Light Pollution has become a major concern in the recent years. Many studies try to
quantify this phenomenon as accurately as possible. This article presents the results of a study that enables the rigorous calculation of upward flux coming both directly from outdoor lighting luminaires but also from illuminated surfaces by reflection.
Many authors have already conducted studies including the quantity of reflected flux from illuminated surfaces in order to quantify the total upward flux that is emitted. This paper uses interior lighting calculation technique in order to quantify with a fixed and high level of accuracy this flux by integrating all the light coming from illuminated surfaces outdoor. Compared with the recent contributions on this matter, it brings a further precision on the reflected flux and therefore enables an improved knowledge of the phenomenon.
Light pollution in Germany – the legislative situation
Dr. Andreas Hänel, Am Schölerberg 8, D-49082 Osnabrück, Germany, ahaenel@uos.de
Czechia on the way to sustainable lighting
Jan Hollan, N. Copernicus Observatory and Planetarium in Brno, Kraví hora 2, CZ-616 00
Brno, Czechia, jhollan@amper.ped.muni.cz
In the course of one year the light pollution became illegal in Czechia, from the very idea to include it into the Clean Air Act till it became valid June 1, 2002. The idea and the key work to make it true is due to Stanislav Fischer, an astronomer who had been a member of the House of Representatives for many years. The background info, the proposed wording of the law and endorsement letters have been submitted to the House by the Czech Astronomical Society. Astronomers acted as environmentalists with the best understanding of the broad problem, thanks to their natural interest in the protection of the night. Environmentalists from other professions begin now to be interested as well. For each pilot project to make the outdoor lighting sustainable in a small area at least, a fully devoted person is necessary. I hope some will emerge within national parks or municipalities, in addition to some observatories. As the problem is very new for most of the Czech population, the issuing of concrete measures to start a pronounced decline of light pollution has been postponed by the Ministry of Environment. The current discussion gave no arguments against a Lombardy-like measures. At the moment, obeying the law cannot be enforced. This is may be not bad, as a voluntary adherence to the law helps to raise the public awareness and responsibility.
One issue which needs to be made clear, is the necessity of the ban of direct emissions above horizon for all strong light sources. Especially the almost horizontal light is harmful, much more than the light going steep upwards. Most of the almost horizontal light comes from the luminaires themselves, not from the lit terrain. Such light contributes most to the unwanted sky luminance and to the ugly appearance of the landscape, kills birds and insects, reduces safety of transport, disturbs sleep of substantial fraction of population.
Another issue is the involvement of local residents into lighting projects. When a building or a monument is to be lit, all the people which would then get more light into their windows should be asked, if their bedrooms are not affected. If yes, the project is to be either abandoned or modified in such a way, that the illumination of bedrooms does not rise — in any case, after the curfew.
Some examples from Brno, both good and bad, are presented. (for more info, see
Protection of the Night Sky in Catalonia
Dr. Ramon San Martin, Diagonal 647 pl. 10, E-08028 Barcelona, Spain,
ramon.san.martin@upc.es
Catalonia, a Country in NE of Spain, has developed a law for the protection of the sight sky. The deployment of the law, and now its application, had been accompanied by studies about the situation, problems and solutions, reaching an original methodology for analysis and quantification of Light Pollution.
The paper describes this process of study, elaboration and application, the methodology developed, and also some interesting conclusions derived from it.
An inventory of skybeamers in Germany
Winfried Kräling, Marburg, and Dr. Andreas Hänel, Am Schölerberg 8, D-49082
Osnabrück, Germany, ahaenel@uos.de
Mainly amateur astronomers (but also other people) complain about the increasing number of so-called skybeamers, searchlights used for commercial advertising or special events. These powerful concentrated often moving light sources contaminate the sky over large areas and prevent visual and mainly photographic astronomical observations. Therefore the DARK SKY group of the German Vereinigung der Sternfreunde made a call to report sights of these skybeamers. We report first results and discuss the distribution in Germany.
How many stars can we still see?
First results of a simple light-pollution experiment
H. Pikall, Institut für Astronomie, Türkenschanzstrasse 17, A-1180 Wien, Austria
G. Wuchterl, Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse, D-85748
Garching, Germany
M. Netopil, J. Hron, Th. Posch, N. Zeitlinger, Institut für Astronomie, Wien
We present the results of a nationwide light-pollution awareness and observing campaign carried out during the ”Science Week Austria 2001”. Data were obtained by issuing a public call via print media, broadcast & internet and by distributing images of Ursa Minor for 7 different limiting magnitudes (1.5 … 6.5).
Observers compared Ursa Minor as visible under local conditions with the reference images and supplied observing time and location together with an identifier for the image that fitted their observation best (i.e. e. that corresponds to their local limiting magnitude).
To access the quality of the data, we called for observations in an interval containing a significant fraction of the nautical and astronomical twilight. Reports where collected via the Website
We present the results obtained so far, yielding an empirical visual limiting magnitude map of Austria, and estimate the accuracy by the twilight dependence plus a comparison with Walker’s law for the case of Vienna. The median visual limiting magnitude of 1700 reports was 4mag. Magnitude 6 observations typically have been reported from a distance of about 100 km from the city of Vienna (pop. 1.8 Mio) with the respective number for Linz (pop. approx. 300 000) being in the range of 40 km.
The brightness of the night sky in urban areas
Dr. Thomas Posch, Institut für Astronomie,Türkenschanzstrasse 17, A-1180 Wien, Austria,
posch@astro.univie.ac.at
We used a 56x85mm! solar panel with an amplifier and an ADC converter to determine the brightness of the night sky in urban, suburban and scarcely populated areas during the summer 2002. In the spectral range where our polycrystalline silicon detector is most sensitive (i.e. e. around 650nm), we could achieve sensitivity in the order of magnitude of 1 millilux. An equally sensitive illuminance meter has been used for calibration.
The first results of our measurements of the night sky brightness in Vienna are encouraging with respect to the usefulness of the applied technique, but very discouraging and alarming with respect to the inferred level of light pollution. At a distance of 4km from the centre of Vienna, we found that the clear night sky (at a zenith distance of 45° and in the direction of the city) does not get darker than it is at the end of nautical twilight (i.e. e. when the sun is 12° below the horizon).
We discuss the implications of these results and compare them with measurements of the twilight and night sky brightness in regions with small light pollution.
The Fight against Mountain-Lights for Advertisements
Dr. Ekkehard Stuermer, Fliederweg 63, CH-3661 Thun, Switzerland, stuermer@sis.unibe.ch
A public campaign has prevented the additional lighting of the Stockhorn (Berner Oberland) summit for advertisement purposes. The Stockhorn is a prominent mountain near Thun. Since 1969 it is accessible from the south by cable car and marked by a bright lamp on the summit.
In 2001 the cable-car company had a tunnel drilled through the mountain to allow visitors easy access to the view north. Subsequently, the windows of the tunnel in the north face of the mountain were outlined by lamps giving the impression of glowing „eyes” (8 fluorescent lamps at 54 W each). What might have been taken for a harmless advertisement gag turned out to be veritable light pollution on long- exposure photographs. Since the cable-car company had failed to apply for the necessary approval the lamps had to be switched off pending official authorization. This was denied recently – but not because of the light pollution but for aesthetic reasons. One argument cited in favor of the lamps actually built on their „similarity to bright stars”! So the silhouette of the Stockhorn and the accompanying chain of mountains will remain unmarred except for the previously existing summit light.
But although this battle may be won and over the next is already there: Photographs show the polluting effect of a security light at a horse corral.
