HUMAN pollution of the natural world is one of the sad truths of modern civilisation. In 19th and 20th century Britain, the emission of smoke and toxic fumes from coal burning and heavy industry was a huge problem.

Organochlorine pesticides almost finished off our birds of prey in the 1960s, while lead additives to petrol were causing us major health problems. We have all but solved these problems now but pollution is still with us – today’s though is less obvious and, if anything, more difficult to deal with.

Thanks in the end to David Attenborough‘s Blue Planet 2 series, we are all much more aware of the plastic problem and those greenhouse gases carbon dioxide and methane are hardly out of the news at the moment. One modern pollutant that hardly gets a mention, admittedly because it couldn’t be described as life-threatening, is light.

Modern human civilisation produces vast amounts of artificial light to allow us to continue with our busy lives during the hours of darkness. The cumulative sum of all the street lights, house lights, car headlights, security lights, stadium floodlights and many more, is enormous.

You only have to travel over Blakey Ridge at night to appreciate the effect; when driving from Kirkbymoorside, Middlesbrough is hidden behind the hills to the north-west, but an eerie orange glow in the sky above gives away its position clearly. Imagine the amount of light that escapes into the atmosphere over Manchester, Birmingham or London. So what? I can hear you saying. Yes, light pollution can cause urban birds’ body clocks to go haywire, resulting in them singing all through the night, and migrating animals can mistake especially bright lights for the moon, causing navigational problems, but these are minor issues really. For many people, me included, the saddest consequence of light pollution is the loss of our view of the night sky.

A cursory glance at an online light pollution map of the UK reveals that we are relatively fortunate in Ryedale. Away from towns our region falls within a green shaded area indicating only moderate light pollution and, on clear and moonless nights, the chance of seeing the Milky Way. Or should I say, the rest of the Milky Way, because we (and our sun, moon and neighbouring planets) are part of it.

To quote those funny chaps from Monty Python, we are travelling “In an outer spiral arm, at 40,000 miles an hour, of a galaxy we call the Milky Way”. It earned this odd name because most of its 200 billion stars are too dim to be seen separately with the naked eye; what we see is a faint and hazy band of light stretching right over our heads from horizon to horizon.

Last winter I attended a stargazing event put on by the Dark Skies Festival team. We met at one of the darkest parts of Ryedale, deep in the heart of Cropton Forest – officially one of England and Wales’ 17 dark sky discovery sites.

A fascinating introductory talk was given by Richard Darn, an expert local astronomer, after which he took us all outside, wrapped up warm in a clear and frosty night, to gaze through telescopes at the wonders above. Serenaded by the hooting of tawny owls we took it in turns to study the rings of Saturn, the moons of Jupiter, thousands of the stars making up the “milk” of the Milky Way and even some distant galaxies beyond our own.

If you would like to take part in this years Dark Skies Festival it runs from February 14 to March 1. For more information, go to darkskiesnationalparks.org.uk