Nation Goodbye, darkness: Light pollution has increased 49% over past 25 years, study finds September 15, 2021 Doyle Rice, USA TODAY Comments Off on Goodbye, darkness: Light pollution has increased 49% over past 25 years, study finds Earth's night sky really isn't as dark as it used to be. Global light pollution has increased by at least 49% over the past 25 years, a study finds.