Sign up for our free weekly IndyTech newsletter delivered straight to your inbox
Sign up for our free IndyTech newsletter
Stars are disappearing from the night sky before our eyes, astronomers have warned.
Every year, the sky gets as much as 10 percent brighter, according to a major new study. This means that vast numbers of stars that were once visible are now hidden from astronomers and the public.
A child born under 250 visible stars, for example, could only see 100 of them by their 18th birthday, scientists warn.
The light pollution blocking these stars is growing much faster than we realize, even with efforts to contain it. And it can have drastic results, not only for the visibility of the night sky, but also for the environment, with effects on the biological systems of animals and humans, and much more.
These are the findings of a major new study which analyzed more than 50,000 observations by citizen scientists around the world made between 2011 and 2022. It aimed to fully understand the scale of the problem of “sky aurora”, or diffuse light in the night sky , caused by human-made pollution.
Until now, changes in sky brightness have been little documented because there is no easy way to gather information from around the world. To address this, the scientists used information taken from an app that collects the view from locations around the world and puts it together.
This data can be used to gather data for the “limiting magnitude to the naked eye”, which measures the minimum brightness an object must have in the sky if it can be seen. As the night sky brightens with pollution, these objects must get brighter and brighter to be seen – or they will disappear from the sky.
These measurements show that the brightness of the sky has increased by 9.6% each year. Previous estimates collected from satellites showed that the brightness increased by only 2 percent.
Satellites have been used to assess the scale of the problem, but suffer because there are none that can observe the entire Earth to account for the ways people see the sky. They are also less likely to see light that emerges horizontally, such as from windows, but these sources greatly contribute to light pollution as seen by people on the ground.
An article on the findings, “Citizen scientists report global rapid decline in star visibility from 2011 to 2022,” is published in the journal Science.
In their conclusion, the researchers note the importance of citizen scientists in providing such data. But they also called for the data to be used by policymakers, noting that existing attempts to curb the problem of light pollution are not stopping the problem from getting worse.
Add Comment