May 4, 2020: Nobody likes a lockdown–except maybe Mother Nature. With many industrialized countries paralyzed by the coronavirus, air pollution has dropped, seismic activity has waned, and wildlife is reclaiming some territory. Frankie Lucena of Puerto Rico points out another effect: “Night skies are darkening,” he says.
“I prepared these images to show how the COVID-19 lockdown has dramatically decreased light pollution in the US and in Puerto Rico,” says Lucena.
To investigate the change in light pollution, Lucena accessed nighttime images from the Visible Infrared Imaging Radiometer Suite (VIIRS) on board the Suomi NPP satellite. The instrument’s Day-Night band is excellent at detecting urban lights, moonlit clouds, and auroras. Dramatic changes in urban lighting have clearly happened during the past month as normal commerce and travel have slowed. The data are available here.
“As a night sky photographer and astronomy enthusiast I embrace this change,” says Lucena, “but I do wish it was under better circumstances.”