Reaching for the stars
PUBLISHED: 11:25 17 February 2015 | UPDATED: 11:35 17 February 2015
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Light polution is obscuring our view of the heavens. Liz Hamilton of Campaign to Protect Rural England Hertfordshire says while the county is taking steps to curb it, more can be done
When did you last see the Milky Way, that pale band which appears to arch across the night sky, formed from many billions of stars which make up our own galaxy? In Hertfordshire, this might be possible only in the most rural areas. Elsewhere in the county, ‘pollution’ by night-time light from many sources spilling into the sky obscures it altogether.
Towards the end of August last year while staying in the Northumberland National Park, I enjoyed on a clear warm night the intensely starry night sky in all its glory, with the Milky Way beautifully clear. It took my breath away. It was a reminder of how much we are missing in our home county.
Today many younger people may grow up rarely or never seeing a really dark starry sky. Past generations would have had a closer connection with the heavens. In his Victorian novel Far From the Madding Crowd, Thomas Hardy has his shepherd hero Gabriel Oak tell the time by the stars, and appreciate the night sky ‘as a work of art superlatively beautiful’.
A really dark sky helps to distinguish rural areas from urban, and with light pollution steadily encroaching further into the countryside the Campaign to Protect Rural England is a leading voice among organisations trying to stop and even reverse this trend.
The group published satellite maps in 1993 and 2000 which showed for the first time how much light was shining up into the night sky. The data revealed that light pollution increased by 26 per cent in England in those seven years.
Following a successful decade-long campaign by CPRE alongside the British Astronomical Association’s Campaign for Dark Skies, a planning policy to control lighting was introduced in the National Planning Policy Framework in 2012.
A CPRE survey of English local authorities in April last year (published in its report Shedding Light), revealed how two Hertfordshire authorities are tackling light pollution. The county council, responsible for more than 118,000 street lights, now turns off 75 per cent of them between midnight and 6am. The exceptions are along A roads and some pavements and in known crime hotspots. Introduced in 2011, this policy saves nearly £1.4m a year and achieves substantial reductions in carbon output and upward light pollution. Initial concerns that levels of crime would increase as a result of the policy seem unwarranted; none of the authorities responding to the CPRE survey experienced increases in reported crime as a result of these switch-off policies.
In the west of the county, Dacorum Borough Council will wherever feasible consider the lighting implications of all development and road proposals, aiming to minimise new exterior lighting, especially in rural areas and urban fringes.
Returning to Northumberland National Park, it has achieved international status as a ‘Dark Sky Place’, while at the other end of England, the Isle of Wight, supported by local CPRE campaigning, is aiming for a similar designation, which is valued by astronomers and helps to boost tourism. Here in Hertfordshire we are unlikely to achieve such a status, but we can still do much more to control light pollution and protect those places which still have darker skies. This includes ensuring that outside lights shine only downwards and are turned off except when needed.
During February for the past four years CPRE’s national star count has revealed a continued increase in light pollution. Asked to count the stars within the constellation Orion, the number of participants unable to see 10 or more (indicating severe pollution), rose from 54 per cent in 2013 to 59 per cent in 2014. In the same year only four per cent of participants saw more than 30 stars in Orion, suggesting they enjoy a truly dark sky, down from five per cent the previous year.
Now CPRE nationally is seeking funds to produce new satellite maps to reveal present-day light pollution levels, aimed especially at providing robust evidence about lighting levels in each local authority area, informing local decisions about lighting and promoting protection of our remaining dark sky heritage. Go to cpre.org.uk to discover more about how you can tackle light pollution.
February might be dark and cold, but there is a plus side to these conditions: wrap up warmly and indulge in some star gazing (best when the moon isn’t too bright). Without any special equipment you could start by looking for two constellations:
The Plough or Great Bear, or as Thomas Hardy calls it, Charles’s Wain, looks like a giant saucepan. It’s special because you can use it to find north. This may no longer be essential to get you home, but in the past helped people on land and at sea to find their way. Draw an imaginary line through the side of the saucepan away from the handle and follow the line upwards until you see a very bright star – the Pole Star. Face it and you are facing north.
Orion (the hunter) with his central belt of three stars, is a very distinctive feature in the night sky, especially from January to March. The constellation includes two of the brightest stars in the sky, Rigel and Betelgeuse. These, the belt stars and two others form an hourglass shape.