What’s your favorite stargazing memory?
For thousands of years, we humans have depended on the night sky for navigation, storytelling, and as a catalyst for the big questions about who we are and why we’re here. Now, this wonder of our world is being threatened by light pollution, and it’s doing more than just making it difficult to see the stars. Light pollution can have a huge toll on our health!
What is light pollution? Well, the International Dark-Sky Association (IDA)—we’ll introduce you to them in a second—define it as “the inappropriate or excessive use of artificial light.” Excessive light has an enormous impact on humans, wildlife, and even the climate.
Light pollution shows up in a few ways, some common ones are:
- Glare: excessive brightness that causes visual discomfort
- Skyglow: brightening of the night sky over inhabited areas
- Light Trespass: Light falling where it is not intended or needed
- Clutter: bright, confusing, and excessive groupings of light sources
(International Dark-Sky Association)
Any of these sound familiar? It probably does, because 80% of the world’s population lives under light-polluted skies! And if you live in the United States or Europe, 99% of the population lives with light pollution. (Science Advances)
What’s the impact of this light pollution? For animals, artificial light at night can cause disruptions to migration patterns, spawning behaviors, and feeding habits.
In humans, the effects can be pretty terrible as well. Exposure to excessive light can alter our sleep and wake cycles, core body temperature, hormone regulation and release, and patterns of gene expression. These could potentially have impacts on human health like breast and prostate cancer, obesity, diabetes, and depression. (The Royal Society)
Environmentally, a lot of wasted energy goes into keeping the lights on at night. The IDA estimates we waste about 30% of the lighting we use.
What can any of us do about this? Well, we have a great thought leader to introduce you to that will leave you excited to tackle light pollution in your own world!