One of the things that attracted us to this place back in 1997 was the lack of light pollution. We came house-hunting in April that year and enjoyed skies of cloudless blue in the daytime and inky velvet at night, peppered with countless stars. A comet that was the merest smudge on the London skyline arced across the night sky here, its tail quite distinct.
Fast forward 16 years and we are still in the happy position of being able to see the Milky Way clearly and pick out the constellations without difficulty – well, the ones we know, anyway. Friends living in the Célé Valley in the Lot claim their area is one of the least light-polluted in France. However, over that time, many local villages and hamlets have installed street lighting. We can see two from our house at night where previously there was almost nothing.
Clearly, people are concerned about security and crime and street lighting is, to a certain extent, a deterrent. It also helps people find their way around on foot more safely. But the halo effect dims the starlight. Apparently, light from a big city has an effect 100km away. Moreover, street lighting consumes energy and money, is disruptive to wildlife and potentially to human biological rhythms, too.
Local communes are responsible for street lighting and they can do plenty to counter its harmful effects without having to get rid of it altogether. This includes:
- Installing streetlights that angle the light downwards to the pavement rather than upwards;
- Switching lights off in the small hours and reducing the duration of Christmas lights;
- Using energy-efficient light bulbs.
A national association – Association Nationale de Protection du Ciel et de l’Environnement Nocturne (ANPCEN) – has run a competition for the past few years to encourage communes to save energy and reduce light pollution. According to ANPCEN, street lighting accounts for 38% of communes’ annual electricity bills and 48% of their electricity consumption in kWh. ANPCEN give communes a star rating – what else? – from one to five and the designation ville/village étoilé(e).
I was pleased to note that of the 216 communes listed, two villages not very far away are villages étoilés: Beauregard (Lot) has four stars and Vidaillac (Lot) has one. I was less pleased to note that not a single place in Tarn-et-Garonne is listed. But the scheme is, of course, voluntary. And the 216 communes represent only a fraction of the c. 36,500 communes in France métropolitaine.
The website also includes an interesting map of light pollution in France. [For some reason the link doesn’t take you directly to the map but to the home page. On the home page, click on ‘Pollution lumineuse’ in the top bar and then on the 3rd item on the drop-down menu, ‘cartes de pollution lumineuse’]. While I know there are all sorts of caveats about how to measure this, greater Paris, Bordeaux, Toulouse, Lyon and the agglomeration around Marseille stand out very clearly. You can also click on your département for more local detail. We are in the north-east of our département, which is comparatively rural and far from any big towns, so the chances of seeing the stars are greater here.
The government has also passed a law requiring businesses to switch off exterior lighting and signs by 1 am, which it is introducing progressively.
Sadly, since the weather has reverted to type, we won’t be doing a lot of stargazing in the immediate future.
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