One of the greatest inventions of all time. It guides us and helps keeps us safe. We cannot imagine our lives without it. However, its pollution is creating health problems, it is causing wildlife to change its behaviour, it is negatively impacting our heritage sites and it is contaminating our night skies. It’s on the increase in Malta and it will keep getting worse until each one of us takes action. The source of this pollution? Artificial light.
Light pollution is the excessively bright and unnecessary use of artificial light. This includes both exterior and indoor lighting, marketing billboards and screens, as well as buildings and structures illuminated by a lot of light such as schools, football grounds, churches, shops and office buildings among others.
Back in the day, if you looked up at the night sky, you would have been able to see millions of stars and the milky way. How many of you have seen the milky way? There’s no need to use the internet. It’s there, right above us. But if you’re like me, you’ve never had the opportunity to see the band of stars with your own naked eyes. Nowadays, if you’re at home looking up at the night sky, you have to strain your eyes just to make out the brightest stars.
So why can’t we see the milky way? It’s because the world is bathed in light. Just take a look at the image below which shows the levels of brightness of the night sky in our islands. The colours indicate various levels of brightness. The brighter the colour of an area, the more difficult it is to see stars. The research article which contains this map highlights how 88% of Europe experiences light polluted nights! And, as you can see, no place in Malta is protected from this source of pollution. You need to venture out far away into the Mediterranean sea to get away from it.
The image is taken from a map which is based on data published on June 10th 2016 by a team of researchers led by Fabio Falchi. The research article can be found here: https://advances.sciencemag.org/content/2/6/e1600377
Map Credit: Falchi et al., Sci. Adv., Jakob Grothe/NPS contractor, Matthew Price/CIRES. | https://cires.colorado.edu/Artificial-light
A recent research study led by astrophysicist Dr.Joseph Caruana has shown how a huge part of the Maltese Islands are heavily polluted with light. The study shows how the worst affected areas are Birkirkara and the Freeport area in Malta, and Victoria and Għajnsielem in Gozo. You can take a closer look at the local map here: http://www.nightskymalta.info/ and you can also read the full research paper here https://arxiv.org/pdf/2002.04435.pdf
Some may ask “So you’re telling me that I need to switch off my outdoor lights just so that we can see the stars?” Partly yes but not just for that- reducing night sky brightness is also beneficial to wildlife and for our health.
How does light pollution affect our health?
How many of you can’t fall asleep straight away when going to bed? I know of people who have said that they take an hour or more to fall asleep. One of the reasons why this is happening could be as a result of artificial light.
Take mobile phones as an example. Most people know that you shouldn’t look at your phone’s blue screen before going to sleep as research has shown that it affects our sleeping patterns. To solve this problem, phone manufacturers are nowadays including a blue light filter.
But this blue light does not just light up our phone screen. It’s also used to brighten our computer screens, televisions, and is sometimes also used to light up our homes and our streets. Bright white/blue light puts us on the ‘alert’ – it’s the kind of light that is good to have during daytime, but not suggested for night-time. This light, so late at night, disrupts our sleeping patterns since we’re more sensitive to it. When we expose our eyes to this light, we’re literally telling our brains to wake up…and we all know how lack of sleep leads to headaches, stress, tiredness and other health problems.
Let’s also not forget that unless you live in the countryside, most of us have outdoor light coming in through our windows at night. Yes, buying light blocking curtains will help solve this problem. But what if we could work as a community to switch off unnecessary outdoor lights at night? Starting with us, and hopefully inspiring local councils, organisations and businesses to do the same? The solutions could vary; either changing street-lamps to warmer light, shielding them and even considering diming them.
But what does light pollution have to do with wildlife?
Look at it this way, for billions of year Earth had a cycle: light during the day, darkness at night. Animals and plants have evolved and adapted with this natural cycle. But by using artificial light, especially a lot of outdoor lights, we are disrupting this cycle. And this means that animals that are dependent on the darkness of night are being negatively affected; this includes their sleeping cycles, their protection and also their reproduction success!
Let’s take as an example nocturnal animals. These animals sleep during the day and wake up at night to hunt and mate. Nocturnal animals which are predators need light to hunt, and nocturnal animals which are prey need darkness to hide and protect themselves. By changing the cycle of light, we are inevitably favouring predators and taking away the protection of their prey.
Night-time lights also affect birds – artificial lights at night attract and confuse migrating birds, making it easier for them to smash into building or glass to the ground below. Locally, young shearwater birds have been known to get confused and to make their way inland towards the light instead of going out to the sea to fish.
Sea turtle babies that depend on the moon light over the sea horizon to guide them to the safety of the sea may instead wander towards beach lights or city lights causing them to dehydrate and die when the sun comes up in the morning.
So what can we do?
Every little helps! Small changes can have a big impact. Here a few things which we can do to help reverse the negative impacts of light pollution:
Enjoy the night sky first-hand
What do you need to start your astronomy journey?
Choose a night when there isn’t a full moon in the sky and check the cloud coverage using a website such as https://www.windfinder.com/
Location, location, location. The location you choose is key to the success of your stargazing experience. Check out which areas are least polluted using the map on http://www.nightskymalta.info/
There are numerous websites with freely downloadable maps of the sky. One of these websites is http://skymaps.com./downloads.html
You need to download a northern hemisphere map for the month when you’re going stargazing.
If you prefer using your phone instead of an actual printed map, there are lot of apps free of charge on the app store which you can choose from.
Have you ever noticed that when you switch off the light at night you see nothing at first, but after a while you’re able to make out what’s around you? The pupils in our eyes are amazing tools that can contract and dilate depending on how much light you need to let in your eyes. To be able to enjoy the night sky, you need to be able to see in the dark.
Our eyes take around 5 minutes to adjust to the darkness and any white light source, including that of our phones, interferes with our eyes. In fact, if you’ve ever attended one of the Astronomical Society of Malta’s event, you’ll notice that the astronomers leading the events usually use red light to see.
You can make your own red flashlight by covering a normal flashlight with multiple layers of red plastic (you can fold the plastic sheet over itself as well instead) and using a rubber band to hold it in place. Another option is to use a red soft drink bottle cap on top of your flashlight if you have small flashlight available at home.
When you switch it on in the dark, your torch needs to shine a deep red colour. Try out your red flashlight at home at night to see whether you’re able to read your star map.
The sky changes throughout the year as the Earth orbits the sun but Polaris is a star which is visible throughout the whole year in the northern hemisphere. Which makes it the perfect star to start your stargazing experience!
When going stargazing, please be considerate of both the local wildlife as well as others who might be observing the night sky. Always dim your car lights when approaching observation sites.
Don’t forget to take comfortable chairs and a bin bag for any snacks that you take with you. Dispose of your waste responsibly when you get back home.
Join a local astronomy group!
Want to join astronomy events, or participate in a course? For a small fee you can become a member of The Astronomical Society of Malta by filling in an online form. https://www.maltastro.com/joinus
The society also organizes free events open to everyone, even those who are not an official member. So keep a look out for any upcoming events on their facebook page or website.
Stellarium Astronomy Software
You can also enjoy the wonders of the night sky from the comfort of your home. Stellarium is a free to download desktop planetarium which you can use to look at the sky virtually!
To download and install the software visit http://stellarium.org/ and download it from the top bar.
Did you manage to find Polaris? Let us know on social media using the hashtags #esplorastronomer #esploramalta
