Look up at the sky and count the stars

The Milky Way visible over St Thomas a Becket's church, Romney Marsh
The Milky Way visible over St Thomas a Becket’s church, Romney Marsh: Photo by Zoltan Tasi on Unsplash

Shelly Dennison ponders the starry sky:

The wonder of a star filled sky has inspired writers, artists, scientists and theologians for centuries. Alister McGrath opens his book The Re-enchantment of Nature, Science, Religion and the Human Sense of Wonder with “As a child, I found myself fascinated by the mysterious patterns of the constellations, the faint glow of the Milky Way, and the slow movements of the planets across the night sky.”

We can follow stars through the Bible, from Genesis 1 and Creation, through the Psalms to the familiar story of the Magi in Matthew’s Gospel. In Genesis 15:5 we read He took him outside and said, “Look up at the sky and count the stars—if indeed you can count them.” Then he said to him, “So shall your offspring be”, a powerful image of one man looking up at a star filled night sky and seeing the world afresh.

Many of the UK’s National Parks have been awarded International Dark Sky Reserve status and run festivals and events to help people discover and learn about the night sky. We may instinctively feel that experiencing starry skies is good for us, a way of connecting to wonder of creation, but there are other reasons to look to limit light pollution on the night sky.

Perhaps the most obvious is cutting carbon emissions. Figures suggest that lighting could account for as much as 30% of some councils’ carbon emissions. Researchers are also investigating the impact of light pollution on nature. Moths, which play an important role in pollinating flowers during their nocturnal activity and have declined in abundance by 40% in the last 40 years, might be being disrupted by light pollution. The moths are drawn away from visiting flowers as they are attracted by street lights – this means less pollen is carried by moths in lit areas.

In a UK based study lasting over a decade, scientists looked at the timing of bud opening in trees, and matched it up with satellite imagery of night-time lighting. After controlling for urban heat, they found that artificial lighting was linked with trees bursting their buds more than a week earlier. Early bud opening means that trees become more vulnerable to frost and diseases. Researchers looking at woodlands believe that early bud bursting will have a cascade effect on other organisms whose life cycles work in synchronicity with the trees. The Winter Moth which feeds on fresh emerging oak leaves is likely to be affected, less moths may in turn have an impact on birds in the food chain that rely on it for food. Other studies have looked at the impacts on migratory birds, frogs and toads.

It is, however, important to note that separating out the impact of artificial light on plants, pollinators and other wildlife from the impact of other factors such as climate change, pollution and habitat fragmentation is difficult. Many species face multiple threats so it’s important to consider how all the issues connect together.

Every February CPRE, the countryside charity, runs Star Count. Star Count is a citizen science project that maps the impact of light pollution by asking people to count how many stars they can see in Orion with the naked eye. The results are used to help people find the best places for stargazing and to inform public policy.

The 2022 Star Count results showed that light pollution was continuing to fall from its 2020 peak. They suggested that severe light pollution, defined as being able to see 10 or fewer stars with the naked eye, had continued to fall. After peaking in 2020, when 61% of participants reported seeing 10 stars or fewer, severe light pollution fell to 51% in 2021 and continued its slide in 2022, to 49%.

CPRE thinks that we are seeing office-based organisations switching to permanent home working, and this, coupled with employers’ desire to reduce electricity bills, appears to have led to fewer lights being left on overnight. This, alongside households being more conscious about wasting energy and councils both reducing street lighting and switching to better lighting design, are believed to be behind the continued reduction in light pollution.

But what’s the picture in 2023? That’s what this year’s Star Count wants to discover.

You can find out more about the project and how to get involved in Star Count 2023 by visiting the CPRE website.

There’s also a family activity pack available for download.

Shelly is Digital Engagement Officer for CPRE Bedfordshire, the countryside charity. She is the Eco Church lead at Putnoe Heights Methodist Church (which is working towards a Silver award). Shelly is a graduate of the CRES course.