Nature's nightlights are disappearing

The night sky in Bacares, Spain. Courtesy of Miriam Espacio.

In songs, in movies, and even perhaps our dreams, stars have become a sort of romantic ideal. We use the “star” to describe charming celebrities, to compliment those we adore, and to decorate the tops of our christmas trees. Stars are such an enchanting idea, we even associated them with the heavens. However, in our lifetimes, it’s completely possible that they’ll disappear from sight.

The change isn’t dramatic, but it’s clear that the sky above us is different than it was a few decades ago. Night skies have abandoned their inky blackness for murky oranges. Cities have gradually incorporated “skyglows” into their aesthetic charm. True “dark-sky” places are shrinking at the same rate as the natural wilds.

​So why exactly are Nature’s nightlights disappearing? It's simple. Light pollution.

An example of a "skyglow". Courtesy of Down to Earth.

Light pollution is defined by humanity’s excessive use of anthropogenic and artificial lighting at night. Put simply, whenever a city seems to have an atmospheric glow, it has light pollution. ​

Light pollution is often overlooked in favor of other environmental concerns (and who can blame anyone? Melting ice caps, burning forests, and dying coral reefs are all equally alarming problems) but it has some very real consequences.

For one, the daily cycle of light and dark directly influences circadian rhythms. It’s already getting harder to sleep with the constant blue light of computer screens and the omnipresent, mounting stress of everyday life. Now the ambient streetlight flowing in through your bedroom window may also become another gatekeeper to a proper night of sleep.

Disregarding human health concerns, the changing night sky can also wreak ecosystems. Irregular circadian systems in animals interfere with natural habits alongside predator and prey relationships.

Specific examples include sea turtles getting confused by coastal lighting and losing their ability to navigate the ocean, migrating birds crashing right into lit sky scrapers, bats missing the optimal time to hunt, and fireflies finding it harder to meet potential mates.

A Satellite View of Paris at Night from the ISS. Courtesy of NASA.

​And who knows? Eventually the chaos in the animal kingdom might even trickle down to human civilization.

​Secondly, the presence of light pollution is a symbol of humanity’s extravagant energy usage. It’s probably not necessary for us to use so much light that the outlines of cities are visible 250 miles away in space.

The main culprit of light pollution is excessive lighting. Many light sources scatter light all over rather than just focusing on the spot they should be, wasting energy and money. Actually, speaking of money, 40% of a city’s electric bill goes to lighting the streets, and half of that is wasted-- this means that America wastes about $3.5 billion each year on unnecessary lights.

Governments have realized this and there has been a push to replace old high pressure sodium lamps with more efficient LED bulbs. The visual difference is startling and sparks hope that light pollution can be combated.

Before (left) and after (right) the 6th Street Bridge in Los Angeles went through streetlight conversion. Courtesy of Vox.

The final reason why the changing night sky is so concerning is a bit more philosophical.

The stars have always bared an existential quality to them. Seeing these giant forces of nature, millions of light years away, still being able to illuminate our dark skies is an irreplaceable experience. It reminds us of our sense of self, our place in the universe. We’re so small in the grand scheme of things, but we still have worthwhile dreams and thoughts. This isn’t just baseless, sentimental musing, either— there have been psychological studies that suggest diminishing stars can also mean a diminishing perception of ourselves.

For as long as the human race has walked the earth, we’ve looked up at the stars. Art, science, and culture has revolved around the sky and its heavenly bodies throughout human history. It’s a bit of a tragedy that there’s a possibility that future generations won’t be able to look up at the night sky and see the stars winking back at them.

As we turn into this new era, the night sky and its stars might not stay with us.

The Advancement of Light Pollution in the U.S. Courtesy of The Skyglow Project.

Visualization of how Light Pollution Affects our Perception of the Night Sky. Courtesy of The Skyglow Project.

---

Angelina Suy is a high school junior in Central California. Alongside a variety of AP and honors classes, she loves to participate in service, culture, and science based clubs and activities including, but not limited to, the Women in STEM Club, Science Olympiad, and Robotics FIRST Outreach. She hopes to pursue Biomedical Engineering after graduation. Angelina hopes that with the Ecolibrium Project, she can spread awareness to help save the natural beauty of the world.