Lit Up Britain: Where Have Our Stars Gone?

On our beautiful planet, our lives are no longer dictated by the natural rhythms of the sun, moon and stars. Artificial lighting means that we can work and play for as long as we like and that the darkness of the night sky doesn’t halt our productivity or enjoyment of activities. In 2020, our towns and cities glow ever more brightly.

What does the research indicate?

We have compared cities across the nation on if the energy they are using compares to crime and light pollution – three widely discussed topics that affect Britain. 

It may not come at any surprise that our capital has the highest rate in energy usage, crime rates and light pollution. However, there are measures we can take to protect our planet and our wallets.

LED lighting is the often preferred environmental choice as it uses much less energy than incandescent bulbs and therefore does less damage to the planet. We can make easy choices in our day to day lives to combat skyglow and light pollution, as even switching off lights that are not in use or fitting motion sensors to essential outdoor lights can make a big difference.

Fitting dimmer switches to LED lights is a fantastic way of maximising energy savings and minimising light pollution. Dimmed LEDs produce significantly less heat than incandescent lights. They also retain their colour regardless of how low their light output is.

Skyglow can be managed with better-designed lighting and buildings that only direct light into a specific area, rather than allowing it to be thrown upwards and contributing to skyglow. We should always be choosing LED Lighting over traditional bulbs and placing them intelligently to prevent as much light leakage as possible. Schemes to dim street lighting or only have street lights turned on at a specific time could also be helpful.

Energy usage effect on light pollution – how do we compare? 

Although the UK doesn’t make the top ten lists for most light-polluted cities or urban areas globally, skyglow in Britain is still a serious issue. We should be able to see approximately 5,000 stars from earth in a clear, dark sky, but in the UK, around 55% of people can’t even see the Milky Way. In 2019, the Campaign for Rural England found that only 2% of people could see truly dark skies, enabling them to count more than 30 stars. 

The highest average brightness value area in the UK is unsurprisingly London, followed by Leeds, Birmingham, Manchester, Liverpool and Newcastle. Business districts like the City of London and facilities including Leicester football stadium also cause significant light pollution. 

Regionally, inner London ranked the highest for brightness and energy usage. However, although the North East has a worryingly high brightness value still, energy usage was one of the most efficient in the country. The South East, in comparison, was the opposite – they produce much less light pollution, but their energy usage was much higher than their ‘dark area’ counterparts – this may be due to being less densely populated, with more land utilised for agriculture and other forms of industry. 

Based on average brightness levels across the county, Herefordshire is England’s darkest county, and Northumberland has the highest levels of perfectly dark night skies. Both counties are attempting to reduce light pollution by making improvements to street lighting. Scotland, The Southwest and Wales all fared the best when comparing regions – Wales also had one of the lowest energy usages regionally too. 

How is skyglow affecting us? 

According to the 2016 World Atlas of Artificial Night Sky Brightness, 80% of the world’s population lives under skyglow. In the United States and Europe, 99% of people don’t experience natural nights. Once more, in a CPRE nationwide study, only over half of their star counters (57%) actually found they could see ten stars or fewer in Orion, with many stars masked by light from street lighting and buildings.

Professional astronomers measure the dark portion of the sky using a tool called a photoelectric photometer to have a background value they can use to compare their star signal against. However, an easy way to measure skyglow or the brightening of the night sky over inhabited areas, is to look for the Big Dipper constellation and count how many stars can be seen by the naked eye.

Does energy usage have an effect on crime?

Contrary to popular belief, there is no clear scientific evidence that increased outdoor lighting provides a crime deterrent. It may make us feel safer but the majority of studies have found to actually make us safer.

We have found evidence that there is some correlation between energy usage and crime, but not as would be thought. In fact, our study shows that in regions with higher energy usage, crime rates are also higher. Eschewing London, the South East has the second-highest crime rates and energy usage – an interesting notion, indeed.  Scotland, who had the lowest reported crime, also had the lowest average brightness value! 

According to a 2015 study published in the Journal of Epidemiology and Community Health, streetlights don’t prevent accidents or crime but do cost a lot of money. The researchers examined data on road traffic collisions and crime in 62 local authorities in England and Wales. They found that lighting had no effect, whether authorities had turned them off completely, dimmed them, turned them off at certain hours, or substituted low-power LED lights.

In fact, most property crime like burglaries takes place during the day, and crimes like vandalism and graffiti are actually assisted by the placement of street lamps and the lights of buildings. 

The environmental cost of skyglow

Energy usage and light pollution are not only affecting our wallets and not helping our crime rates, but animals, birds and insects are especially sensitive to the effects of light pollution. It’s a little known fact that the UK is home to 18 species of bats, all of them protected. Skyglow and the light from car headlamps can disrupt their feeding patterns and stop them from hunting in certain areas at all, leading to a loss of roosts.

Nocturnal migrating birds often have their rhythms similarly disrupted by light pollution and are at risk of becoming seriously disoriented during migration, causing collisions with buildings. Crop pollination is also affected, impacting our ability to grow food. Insects become confused by bright lights at night and avoid pollinating plants as they would if the night sky was dark. 

Research has also shown that in more brightly lit areas, buds on trees open sooner than they would without this light pollution, meaning that our love of powerful lighting can disrupt the seasons too.

What are we missing out on?

In brightly lit cities, inhabitants are being denied the wonderfully rich experience of simply seeing stars. Most people in the UK can’t see the dazzling collection of nebulae that makes up the Milky Way and many will struggle to pick out Orion in the night sky. By missing out on seeing the stars above us, we are unable to appreciate this incredible part of the natural world that our ancestors have marvelled at for centuries before us. 

Astrotourism, where people travel to darker areas to see stars and phenomena like the Northern Lights, is growing in popularity, meaning that there is a great demand for actually being able to see a more natural night sky. 

On 28th March, London will be plunged into darkness with all non-essential lights switched off in honour of the World Wildlife Fund’s Earth Hour, an initiative designed to raise awareness about environmental issues. This year’s Earth Hour is set to be more popular than ever due to increased concern about the threats our planet is facing. If you can, turn off your lights at 8:30pm and indulge in a spot of candlelit stargazing. 

As major landmarks are left in darkness all over the world, the delights of the night sky will be far more easily enjoyed. For city dwellers, it’s important that stars don’t become another urban legend.