Edition 06 of the Astronomy On-line Newspaper

A New Type of Light Pollution: Searchlights

The problem of light pollution

In EAAE Newsletter #1 - a British teacher-colleague wrote about his students - who lost the sky due to light pollution.

Light pollution is an increasing problem - despite the Rio 1992 World Conference on how to cut down the energy consumption and its implications to the expected Greenhouse effect. One of the Astronomy On-Line Collaborative Projects will deal with light pollution - it is expected to become available within some days.

If you live in a light polluted area - you should not hesitate to adress the problem to your local town municipal. According to the Agenda 21 - a paper agreed on by all nations during the 1992 Rio World Conference - all major towns have to write down an energy saving plan within 1996/97.

Most municipal administrators agree that sending light into the atmosphere is a stupid waste of valuable electric energy - so the Agenda 21 may be a valuable help when fighting light pollution.

In particular one type of light advertising may easily be adressed.

Powerful Searchlights

Within recent years we have here in Denmark experienced a new type of commercials - known as skyspots. These skyspots are a combination of up to several individual searchlights. If applied individually, they resemble the anti-aircraft searchlights used during the Second World War.

In some cases the searchlights in Denmark have been computer controlled, see this photo thus moving across the sky as if it was searching for some particular object.

The commercial effect of these searchlights has apparently been tremendous. On our small island, the local newspaper wrote several articles about people observing UFO objects - then these objects were correcly identified - and suddenly EVERYONE knew the name of this company. What a wonderful effect for the people who put up these searchlights!

During 50 nights my astronomy-interested students and I as well as the amateurs in this geographical area were suffering due to this - I assure you that NO astronomy was possible - even our CCD had problems.

The range of this local searchlight was at least 20 km. And last month another company in the city of Naestved (south of Copenhagen, on the island of Zealand) applied a searchlight with even 50 km range (factory guaranteed)!

Possible developments

The Danish company that distributes this equipment has informed us about new equipment- having up to 80 km range! A lot of commercial junk is now possible - there are apparently no technical limitations. Already now - you may combine searchlights with e.g. speech or music. So imagine the entire sky out to 50 km distance filled with searchlights, that vibrate according to the music inside the local disco!

The next stage will be - sorry to say this - a searchlight called "x-y controlled lasers". Just take a look at this commercial. According to this company it is no problem to write on hills, mountains and even clouds. The range should be at least 50 km!

Imagine - a huge yellow burger projected into the sky - all night - 365 nights a year! Wouldn't this be wonderful?

However, - again - it DOES help to fight! In our own township commercial searchlights are now totally banned by the municipal authorities. This ban was due to the protests by both the Wildlife Association, a large number of individuals, and our astronomy club. This local ban has proved most effective - this summer the local disco tried to start similar 10,000 ECU equipment - after 3 nights it was stopped by the authorities.

Effects on Wildlife

But - considering Denmark and Europe as a whole - there is a significant lack of protection. This is a great pity, not only because of the associated greenhouse effect, but also for our joy of astronomy and the beautiful sky above. These searchlights are believed to be of damage to nature in several ways:

First of all - why should ordinary people cut down their energy consumption if others may fill the sky with huge quantities of light energy ?

Secondly - there have been scientific reports about the effects of these searchlights on wildlife. According to the canadian scientist R. RT. Bjorge (The Field Naturalist - 1987 - page 346-350 - and several references therein), these searchlights may imply severe stress on certain wild birds.

Almost two years ago a group of people and we had articles in a large newspaper - this implied a direct reply by the minister of Wildlife and Nature. An investigation was started by the minister - however - since - not much has happened. So far, Danish Law forbids any light commercials placed in outdoor areas: however, nobody knew about these searchlights while the Nature conservation law was originally passed. So, if you place a searchlight inside a town - and let it send light out to 50 km distance or more - that's technically OK.

Presently, the Danish Wildlife and Nature Association and the Astronomical Society are preparing a joint conference on the topic of light pollution, hoping that Denmark may at last get a useful revision of the Nature protection laws.

A Europe-wide list of searchlights?

So, be aware of both ordinary light pollution and in particular these new searchlights.

It would be very interesting to register these searchlights - are these skyspots only a Danish problem - or are they already seen Europe-wide ? Do you know if this kind of equipment is allowed or not in your country ?

Let me know and I will try to compile a list. I will also forward your data to the Danish Wildlife Association and whoever else is interested and may find such data useful.

Let Us Keep Our Skies Clear!

Mogens Winther
Amtsgymnasiet Soenderborg (Denmark)

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Last update: Nov 5, 1996