Starry, starry night over Cloughjordan

By Dr Oliver Moore

Have you ever looked up at a starry night sky and been filled with awe and wonder at the brilliance of it all? Ever wanted to see Jupiter’s moons, and Saturn’s rings, through a telescope?

At its latest event, a well attended online gathering of the Cloughjordan Dark Sky group, on September 23, the group presented some stories about our origins and the universe alongside Irish mythology around stars. ‘Wonders of the Dark Sky’ also saw presentations on the effects of light pollution and ways to enable better lighting practices.

THE NIGHT SKY

“We are lucky here; in some parts of Cloughjordan we can still experience the Milky Way galaxy and many constellation patterns,” said Vicki Moore of the Cloughjordan Dark Sky group. “I’ve become more aware of the night sky in the last few years, and it has now become a much loved hobby that I can share with others.

“It has brought richness to my life and helps me to connect with nature and its wonders.”

The Cloughjordan Dark Sky group holds events where people come out at night to use equipment such as binoculars and telescope to catch the clear, starry nights in all their glory. It is affiliated with the International Dark Sky Association. The aim of the association is to protect night skies and our heritage of dark skies through quality outdoor lighting for the present and future generations.

MYTH AND FOLKLORE

Myth and folklore of the sky at night was shared during the online gathering, with stories and legends from Ireland and further afield shared. Information on what planets, stars and constellations are clear this time of year was also imparted, with the moons of Jupiter of special interest; these moons are very easy to see with basic equipment also very striking.

The event also included information on light pollution - light where it is not wanted or needed - and how that impacts our health, the environment, wildlife, and our ability to find awe in the natural night. New research from the University of Exeter shows that light pollution has grown by 49% over 25 years globally, and this is only for light visible by Satellite. The true figure, on the ground, is multiples of this, the researchers found, with growth by as much as 270% globally.

This means that, for the first time in human history, most people have never seen the Milky Way in real life. Lighting in itself is not the issue: rather, it is lighting installed without proper shielding and appropriate brightness levels that can cause unnecessary problems. Much light is wasted by being unshielded (and thus splaying upwards unnecessarily) which costs money and wastes precious energy.

LIGHT POLLUTION

Light pollution is becoming a chronic, enduring environmental distress on Earth. The event heard of the effects of light pollution on interconnected web of life from the smallest of flying insects, to moths, bats and birds are all impacted by light pollution. Simply put, insects and other creatures are confused and worn out by excessively bright white lights at night, as it interrupts their experience of day and night.

They thus die easier and earlier, while reproducing less frequently. This and other negative impacts also affect a wider range of plants and animals too. The University of Exeter team cited above, using a huge new dataset, found hormonal, activity and breeding pattern disruptions across a range of species - all of which impacts on numbers and health of species, from trees to insects, birds to bats, and even turtles.

Much bright outdoor lighting is wasted, pointlessly displaying upwards into the sky, while also creating a wide glare which impairs clear vision on the ground. This excessive throw of unnecessary light wastes energy and makes climate targets harder to meet. Appropriate – that’s hooded, directed light – can improve visibility while reducing energy waste.

HUMAN HEALTH

The event also heard of concerns regarding human health and excessive light pollution. Artificial light interrupts our circadian rhythm – out internal time clock. Research is emerging on the body stress caused by over exposure to light at night, especially of LED lighting on the sleep-wake cycle. A 2016 report for the American Medical Association stated that it is “estimated that a white LED lamp is at least five times more powerful in influencing circadian physiology, while “recent large surveys found that brighter residential nighttime lighting is associated with reduced sleep time, dissatisfaction with sleep quality, nighttime awakenings, excessive sleepiness, impaired daytime functioning, and obesity”.

There were solutions presented too however. Small personal steps such as simply making home adjustments were put forward. The use of targeted lighting - shielding lights so they shine down on the ground, using motion sensors, opting for the appropriate warm colour lighting - all help optimise the light experience for everyone. These approaches allow for homes and streets to still provide for safety on the ground while limiting stresses on bodies and the environment. To this end, a colour temperature of 2,700 Kelvins, and ideally no more than 3,000 Kelvins, is recommended by the International Dark-Sky Association, for outdoor street light. The good news is that this rate is within the range of acceptable options in Ireland for street lighting.

FURTHER DETAILS

To be kept informed of upcoming events from the Cloughjordan Dark Sky group, email darksky.cloughjordan@gmail.com.