Saturday, 24 October 2009

Dark sky at night, astronomers' delight

At the end of a garden path, in a home-made observatory overlooking Wee Glenamour Loch, there’s an air of expectancy among a gaggle of astronomers who have gathered. Not because it’s a good night for star-gazing. It’s not: the skies are leaden and the rain is rising in stair-rods. But here on the edge of the Galloway Forest Park, locals are preparing to celebrate its recognition as a Dark-Sky Park, an award unique in Europe, that will rank this lonely corner of South West Scotland alongside just two other areas in the world.

Next month, the International Dark-Sky Association – based in Tucson, Arizona - will convene to ratify the report of its inspectors in Britain. Final tests, which begin tonight in the shrouded hills of Glen Trool, are almost certain to confirm a first batch of readings that registered parts of the vast and lonely forest at Bortle 2 on the international darkness scale. For the uninitiated, Bortle 2 is as dark as it gets on dry land, anywhere in the world; only in the middle of the ocean, where light pollution is entirely absent, could you experience the profound blackness of Bortle 1.

“There will be a little bit of pride. I will be able to say: ‘I live in the dark-sky park’ and I’ll push it for all its worth,” says Dr Robin Bellerby, 69, a former headmaster, and chairman of the Wigtownshire Astronomical Society. “All teachers are missionaries. This can be a solitary hobby , but we like to interest people to join with us and turn their heads up.”

Barring perhaps Cape Wrath, the most remote point of mainland Britain, nothing compares to Galloway for astronomers. Far from large towns and cities – Glasgow and Edinburgh are over the hills and more than two hours away to the north – and with the atmosphere cleansed by frequent rain, the quality of darkness is exceptional.

You don’t need rocket science to explain why the forest park is special says Steve Owens, the UK national co-ordinator of the International Year of Astronomy, and one of tonight’s three inspectors. It’s simple: high quality darkness depends on an absence of light. Light pollution from sodium lamps in the city “is a terrible spoiler for astronomers," he says. “On the clearest night in London, you might be able to pick out only 200 stars.” In Galloway Forest Park some 7,000 fill the sky. Weather permitting.

Sheltered by a stand of pines near the small town of Newton Stewart, Dr Bellerby and his friends feel the benefit. The observatory sits on the edge 320 square miles of parkland in which there are just 414 “points of light”, or houses. When the Forestry Commission contacted the householders asking for their assistance in the dark-sky campaign, all but three agreed to douse unnecessary lights and keep buildings dark.

It is probably helps that, according to legend at least, astronomy is a secret passion for many locals. A couple of years ago, sensors in the roads, that count vehicles, registered a surprisingly high volume of traffic travelling into the forest park in the darkest hours of night. The local constabulary, alerted to possible foul play, descended on a car park by the inky blackness of Clatteringshaws Loch. They found not drug dealers, sheep rustlers or even Stan Collymore and friends; just a group of guys with cagoules and thermos flasks, their telescopes trained on the Crab Nebula

But not tonight, as the rain clatters on the observatory roof. “Won’t see anything, I’m afraid,” says Dr Bellerby, with the cheery demeanour of a man who, for once, is looking forward to a good eight hours sleep.

Last Wednesday, “a lovely night”, he had wiled away the evening totting up the man-made objects he could see above his head: two American military satellites; two pieces of Russian rocket; the international space station – “that’s bloody large” - and a communications contraption. All this in the silent sky above the unsuspecting farmers of Newton Stewart? “Yes, yes,” says Dr Bellerby contentedly. “Two hours after dark you’ll probably see 30 satellites. A deck chair’s super. Just lie there and slowly track them.”

But the real joys come with the Heavenly delights: the Milky way sprawling east to west across the hills; Jupiter, with its moons clearly visible in the southern skies. Or, with the right alignment of sun spots, a stunning display of the Northern Lights. “I never saw it for a couple of years,” said Dr Bellerby. “Then a neighbour rang me. He said, ‘You know how you were complaining about never seeing the Aurora? Get into your garden now.’ And there it was, in all its glory, from west to east and following the coast north. Absolutely extraordinary.”

The final decision of the International Dark Sky Association will be taken on 16 or 17 November. Should Galloway make the grade, the announcement will coincide with the Leonid meteor shower, an annual celestial firework show which promises to be more spectacular this year than it has been for a century. “As if in celebration,” says Dr Bellerby, eyeing the sky expectantly.

I didn't think this article would make the paper. It did, puffed on the front. A shortened version is currently (ie as I post this) the most read article at the timesonline website, Dark Place. Don't these people realise you only get the unexpurgated version on Wade's World?

Photo by James Glossop, who, in the words of Barry Manilow, made it through the rain.

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