Welcome to this edition of Our World.
Our main focus tonight will be on pollution.
We are going to talk about a type of pollution which many people have not even heard of.
Susan Conroy is the Press Liaison officer for the Darker Skies Association.
Susan, could you just give us a few ideas of what, in your mind, constitutes light pollution?
I understand one of the most serious problems is that of light escaping up into the skies above our cities and the result is we cannot see all the stars that were once visible.
That is what I would term a symptom of the problem and not necessarily the most serious consequence.
I would recommend your listeners, if they live in the city area, to go outside, after listening to this program of course, and to look up into the sky.
I would be surprised if any of them managed to see more than five to ten stars.
If they had done this twenty years ago, they would be talking about hundreds and hundreds.
This is a problem that is getting worse.
The whole light pollution situation is deteriorating.
Then, what causes this light pollution, Susan?
Is it just badly positioned streetlights that shine up into the sky?
Well, that is true. Poorly positioned streetlights are a major contributory factor in all of this.
Light pollution is not only light that is shining up into the sky which blocks out the stars we were just talking about.
Light pollution is also when areas are over-lit, for example, or lighting is badly designed or badly positioned, which then creates excessive glare.
This can obviously be dangerous if drivers are affected.
I know so many people are worried about security and I imagine this is why huge areas of our cities are, in your words, over-lit.
Well, many studies have shown there is little connection between lighting and crime.
Besides, much of the lighting which is badly designed creates very strong light and shadow contrasts, which actually creates good hiding places for criminals.
So what changes would you like to see implemented, Susan?
I think there are some very basic things that can be changed.
There needs to be a standard for street lighting which eliminates completely above-horizontal light escape.
By that I mean we can't continue to use inefficient street lighting equipment which enables a lot of the light emitted to escape upwards into the sky.
That is the first priority. Next, we need tougher restrictions on how much light is used to illuminate a given area.
That way, we avoid the problem of what is called light trespass, where light escapes from the area, for example, a parking lot that it is supposed to illuminate, and goes, for instance, into nearby windows or roads.
Yeah, that often happens.
This is what we are saying.
We don't have a problem with security lighting in any number of parking lots or stores.
But, and this is important, the lighting needs to be suitable and, above all, directed correctly.
We are becoming a society obsessed with turning night into day but I can tell you now, not everybody finds this situation satisfactory.
Is there something we can do ourselves to lessen the problem, or at least not add to it?
Yes. There are things we can do in our own home.
For example, if you use lighting, be it security lighting or lighting for your barbecue in the garden, just make sure it is well directed, by which I mean angled downwards, and the light source itself, the bulb I mean, has a good cover on it.
Well I, for one, have learnt a lot this evening.
And you have given us a lot of food for thought the next time we look up into an increasingly orange sky al night. Susan, thanks for your time tonight.
This is the end of the second interview.
Questions 6 to 10 are based on what you have just heard.
Question 6: What does the woman think of light pollution?
Question 7: Why does the woman suggest that the audience look up into the sky?
Question 8: In the woman's opinion, how does lighting relate to crime?
Question 9: What change would the woman like to see?
Question 10: What does the woman recommend for home lighing?