Scientists have warned that the ability of humans to see stars in the night sky could be wiped out in just 20 years because of light pollution.
In an interview with The Guardian, Martin Rees, the British astronomer royal, explained that light pollution conditions have rapidly worsened in the last several years, including since 2016 when astronomers reported that the Milky Way was no longer visible to a third of humanity. He stated that the increasing use of light-emitting diodes (LED) and other forms of lighting are now brightening the night sky at a dramatic rate.
“The night sky is part of our environment and it would be a major deprivation if the next generation never got to see it, just as it would be if they never saw a bird’s nest,” Mr Rees told The Guardian.
“You don’t need to be an astronomer to care about this. I am not an ornithologist but if there were no songbirds in my garden, I’d feel impoverished,” he added.
Separately, Christopher Kyba, of the German Centre for Geosciences, said that a child who is born in a place where 250 stars are currently visible in the night sky would be able to see only 100 by the time they reach the age of 18.
“A couple of generations ago, people would have been confronted regularly with this glittering vision of the cosmos – but what was formerly universal is now extremely rare. Only the world’s richest people, and some of the poorest, experience that anymore. For everybody else, it’s more or less gone,” Mr Kyba added.
Further, the German scientist argued that the introduction of some changes to lightning can make a considerable improvement. These steps include shielding outdoor lights and pointing them downwards, limiting the brightness of lights, and ensuring that they are predominantly blue-white but have red and orange components.
“Mesures like that would have an enormous impact,” Mr Kyba said.
Meanwhile, Professor Robert Fosbury of the Institute of Ophthalmology at University College London (UCL) claimed that the bluish emissions of LEDs entirely lack any red or near-infra-red light. “We are becoming starved of red and infra-red light and that has serious implications,” Mr Fosbury stated.
“When reddish light shines on our bodies, it stimulates mechanisms including those that break down high levels of sugar in the blood or boost melatonin production. Since the introduction of fluorescent lighting and later LEDs, that part of the spectrum has been removed from artificial light and I think it is playing a part in the waves of obesity and rises in diabetes cases we see today,” he explained.
Researchers also noted that light pollution confuses sea turtles and migrating birds, who are guided by moonlight. Additionally, they said that darker nights also provide cover for crime and other dangerous situations for humans.
