Over half the stars we see now won’t be visible in 20 years, study says. Here’s why

Poet and playwright Oscar Wilde once wrote, “We’re all in the gutter, but some of us are looking at the stars.” However, maybe not for much longer.

Many of the stars we see in the night sky — whether from a gutter or a glade — will be blurred from our view in 20 years, according to a study of light pollution published in the journal Science on Jan. 19.

Researchers came to this somber conclusion after analyzing over 50,000 citizen scientist observations over a period of 10 years.

Participants across six continents were given a series of star maps multiple times each year and asked to select the one that best matched the sky at their location.

Based on the results, researchers found that, on average, the night sky grew brighter at a pace of about 10% per year. But, over time this increase compounds, like a bank interest, so after a 10 year period the sky would be 159% brighter.

The growing brightness, like a decades-long sunrise encroaching on the night, is caused by light pollution. Radiating from cars, street lamps and office buildings, our collective artificial glow outshines the dim light of distant stars, hiding them from the human eye.

Our current view of the night sky is “deteriorating” so rapidly that a clear change will be noticeable in a generation, researchers said.

A child born today, while gazing up at the cosmos for the first time, might see 250 stars. By the time the child turns 18, if current light pollution trends continue, only 100 of those stars will still be visible, researchers said.

This rate of “skyglow” is much faster than the rate of light emission growth previously measured by satellites, which cannot detect shorter wavelengths of light, the type of light most likely to scatter around the atmosphere.

‘Easy challenge to solve’

Mechanisms for reducing the ever-growing light pollution are well understood, and they typically involve paring back consumption of electricity, researchers said.

“We managed the ozone hole, acid rain was reduced (in many areas), and the terrible smog of London is no longer like it was at the turn of the last century,” Dr. Christopher Kyba, a light pollution researcher and co-author of the study, told McClatchy News. “In some sense, this ought to be an easy challenge to solve, we just need to use a bit of common sense.”

Despite the simplicity of the challenge, light-reduction measures are rarely implemented on a broad scale, researchers said, meaning current pollution trends are likely to hold.

“There are so many concerns people have in the world. You can’t always impose what you’d like to see happen,” Dr. Constance Walker, one of the study’s co-authors, told McClatchy News. “But it’s so easy to light responsibly. We should all try to use timers, energy efficient bulbs and just less light in general; you actually save money by doing these kinds of things.”

Still, if no changes are made, it’s not clear how applicable the study’s dire projections are to all areas of the globe. The data collected disproportionately came from inhabited stretches in the United States and Europe where light pollution is the most prevalent.

So, while urban dwellers will likely lose sight of many stars in the coming years, it’s possible people in the remote parts of the world free from the glare of city lights might be able to continue gazing at the same night sky.

As to what this disparity might mean for society going forward, researchers can only guess.

“Nearly every human who ever lived before 1900 would have had the experience of going outside at night and being confronted by the cosmos,” Kyba said. “Most people who go stargazing in a really dark area say that they feel very contemplative when they see that - your heart rate probably goes down, and you’re filled with a sense of awe.”

“What does it mean when a formerly universal human experience like that becomes something that only the very wealthy or extremely poor experience regularly?”

The lack of “skyglow” could also impact more than just the human experience. It has “shown to affect plants, animals, and their interactions,” according to researchers.

Record-low percentage of Americans are happy with health care quality, poll finds

Poop trail seen by satellites leads to discovery of new penguin colony in Antarctica

College wrestler vanishes after he’s swept away by ocean wave, California police say

Burger King worker reports manager sexually harassing her — and gets fired, feds say