Restore the dark sky

Posted by: Patrícia Guerra
Date: 2022/04/26
Artificial lighting was a great scientific achievement that has revolutionized the way we live and work. It has become a symbol of the evolution of societies and a way of proudly showing off their growth. On the other hand, humans have underestimated the importance of nocturnal ecosystems, illuminating massively without considering the negative consequences of light emission to the atmosphere.

In addition to preventing us from seeing the night sky (so important to our sense of belonging to the universe), when used indiscriminately at night, artificial outdoor lighting affects human health and can cause serious damage to the environment, fauna, and flora. Excess light also represents an increase in energy consumption, and consequently in increased costs of electricity, effects on climate change, and the depletion of natural resources.
The Bortle Scale is a nine-level numeric measure of the night sky’s brightness. The scale ranges from Class 1, the darkest skies available on Earth, to Class 9, daylight-like inner city skies.
Image credit: Sky Glow Project
We are in the middle of 2022 International Dark Sky Week; an annual worldwide event hosted by the International Dark-Sky Association (IDA) that aims to raise awareness about the negative impact of light pollution in our ecosystem and celebrate the night sky as a shared heritage beneficial to all living beings. So, this week is a wonderful opportunity for people to discover value and appreciate the beauty in the dark.

Many cities and villages in Europe and United States are leading the way in reducing their use of lighting. But we still have a long way to go.
Light Pollution in Europe
Image credit: Nasa
The above photo of Europe shows the great glow of cities and suburbs spilling across the land into the edges of the countryside. The study “The new world atlas of artificial night sky brightness” published in 2016 evaluated light pollution globally and concluded that 99% of the European and North American population live in areas with light pollution and that 60% of Europeans cannot see the Milky Way. To get an idea of how badly we are lighting up in Portugal, recent studies show that we are the worst country in Europe, being the one with the most lighting per inhabitant and per GDP.

The issues caused by light pollution are well known by lighting designers and we have a duty of care to respect and protect the night sky in our projects. To be fully successful, we need a global awareness that light pollution is a problem. We must act now!

To learn more about light pollution, you can watch "Losing the Dark," a short planetarium show and video on light pollution produced by the IDA.