Perma-day

pic from www.darkskydiscovery.org.uk

Everybody likes lights. We are strongly visual creatures and we like to be able to see. Even our enjoyment of night is a lot to do with light - the moon and stars, fireworks, candlelight, buzzy neon.

We've never, until now, been without the dark. Before we had mains electricity, the dark was always there, gathered at the edges of the gas or candlelight, ready to roll back across our vision. We could take the dark for granted, and concentrate on making light.

And boy, did we ace it with electricity. Now we easily push away the night to work and play longer and longer. We soak in our artificial extra daytime as if inhabiting an eternal summer. Perma-day is advancing year by year across the land. Many of us now no longer get to experience night.

But still we've kept our light-orientation, even though light is no longer scarce. Dark is what is scarce now, and getting scarcer. We've peopled it with all manner of dangers: from missing your footing, to muggers and the supernatural, and we believe in our hearts that turning on the light will purge them all away.

Our hearts are wrong. Muggers and burglars aren't cockroaches to scatter in the light. Indeed, plenty of research shows that more street lighting doesn't make you safer, and less street lighting doesn't endanger. After all, criminals need to see to assess their target, select their tools, monitor their escape routes - and good 'security' lighting casts wonderfully deep shadows to lurk in, as well as shutting down the night vision of neighbourhood watchers. Light does not make you safe.

But it does hide the stars. The night sky over most homes in the developed world is the grubby beige of light pollution, instead of spangled velvet. It's a waste not just of energy, but of beauty, and of wisdom. A really clear, dark, starry night, when you can see the milky way and almost sense the 3D depth of the sky, joins you to the universe. If you can look up and see that vast majesty above, it offers a perspective on the current Twitter storm, or a good friend's irritating habits.

By projecting our lights up into the sky, we are walling ourselves off. There's no conspiracy, this wall is something we are all building together - and nobody can take it down on their own. Of course, mother nature may be working on that, but why wait till we run out of power? Let's scale back the civic lighting and encourage better direction of lights onto their subject, instead of allowing them to spill wastefully up to obscure the sky.

Even in suburbia you've probably noticed your moon-shadow once or twice - but have you seen your star-shadow on a clear and moonless night? Have you seen the milky way? They are there too, just waiting for you to make the effort. It's not too late yet - visit http://www.darkskydiscovery.org.uk/ to find out where to go.