Join for a full digest of all the perfect opinions of the week in our Voices Dispatches email
Join to our free weekly Voices newsletter
Stars within the night sky are disappearing from human sight at an “astonishing rate” attributable to rapidly growing light pollution, scientists have warned.
Astronomers imagine a rise in the usage of light-emitting diode (LED) bulbs – that are more energy efficient in comparison with traditional lights – could also be contributing to the trend.
They said artificial lighting, also called skyglow, had increased the general sky brightness at a rate of 9.6% per yr – with stars disappearing from human sight more rapidly than indicated by satellite measurements.
Dr Christopher Kyba, a researcher on the German Research Centre for Geosciences, said: “At this rate of change, a toddler born in a location where 250 stars were visible, would give you the option to see only about 100 by the point they turned 18.”
The researchers said that on a transparent dark night, the human eye should give you the option to see several thousand stars.
But they added that growing light pollution meant that around 30% of individuals across the globe were unable to get a nightly view of their home galaxy – the Milky Way.
For the study, Dr Kyba and his team of researchers analysed greater than 50,000 observations made by citizen scientists as a part of the Globe at Night project run by the US National Science Foundation’s NOIRLab.
They checked out observations submitted between 2011 and 2022, specializing in data from Europe and North America.
Their findings showed a rise in sky brightness at a rate of 9.6% per yr within the last 12 years – much greater than the roughly 2% per yr increase calculated using satellite data, which the team described as “astonishing”.
In accordance with the researchers, this was because existing satellites weren’t well suited to measuring skyglow because it appeared to humans – particularly LEDs.
Dr Kyba said: “This shows that existing satellites aren’t sufficient to review how Earth’s night is changing.”
He added: “Since human eyes are more sensitive to those shorter wavelengths at night-time, LED lights have a robust effect on our perception of sky brightness.
The rise in skyglow over the past decade underscores the importance of redoubling our efforts and developing recent strategies to guard dark skies
Connie Walker, National Radio Astronomy Observatory
“This may very well be one in every of the explanations behind the discrepancy between satellite measurements and the sky conditions reported by Globe at Night participants.”
The researchers said light pollution had many detrimental effects on human health and wildlife, because it disrupted the transition from sunlight to starlight that biological systems have evolved to rely on.
Connie Walker, an astronomer on the National Radio Astronomy Observatory within the US, said: “The rise in skyglow over the past decade underscores the importance of redoubling our efforts and developing recent strategies to guard dark skies.”
The findings are published within the journal Science Advances.