I’ve always loved the night sky. The way the moon glows and casts its light across the darkness. How you can see more and more stars the further you get from the city lights. The mystery of it all. Staring at the moon and stars is peaceful. Sometimes it gives you a sense of nostalgia. Other times, it makes you think about the future — the unknown.
One night, while gazing up at the sky, I noticed something strange: The sky wasn’t completely dark.
It wasn’t because the moon was particularly bright, and it wasn’t because I could see the Milky Way. Instead, a faint, bluish-purple hue spread across the sky.
The sky almost looked as if it wasn’t fully nighttime. It wasn’t bright enough to resemble an Alaskan summer — afternoon light lasting well into the evening — but it was bright enough for me to notice that something was strange. It looked as though daylight refused to let go.
This observation fascinated me.
Eventually, I noticed this hue frequently. Soon, my curiosity got the best of me, and I decided to look into this phenomenon. Someone else had to have noticed it too.
After researching, I learned that this faint glow is normal. It’s caused by a variety of natural factors, our own atmosphere, and the history of the universe itself, as well as a human-influenced issue: light pollution.
If you live in a highly populated area, you may know that the main reason the night sky never seems completely dark is because of light pollution and a phenomenon called “sky glow.” “Sky glow” is the brightening of the night sky, mostly in urban areas, due to car lights, streetlamps, office lights, and outdoor advertising. These artificial lights scatter toward the ground, creating a constant glow above cities.
This glow is so strong that it dramatically reduces the number of stars visible to the naked eye. Studies show that globally, the night sky becomes brighter each year, making it increasingly difficult to experience a truly dark sky.
Light pollution is different from other forms of environmental pollution. Unlike air or water pollution, we typically don’t think about it because electric lights serve important purposes.
Still, learning about “sky glow” made me appreciate how much we can discover through simple observation.
What started as a random question about the night sky turned into a lesson about astronomy, environmental science, and human impact on the world.
Researching topics that genuinely interest me is one of my favorite ways to learn about the world. Observing, asking a question, and learning something new is incredibly rewarding.
I appreciate the convenience of modern lighting, but I hope that in the future, we can find better ways to decrease light pollution. I’d love for more people to experience a truly dark night sky, only illuminated by stars. After all, some of Earth’s greatest beauty appears only after the sun goes down.
Featured Photo by Leonie Zettl on Unsplash.
