Can ultraviolet light kill the coronavirus?18-06-2021
Since the invention and spread of artificial light, alm […]
Since the invention and spread of artificial light, almost no place on earth appears completely dark after sunset. Even in places like Tucson, Arizona, for astronomers, the night sky is illuminated to some extent by artificial light sources.
With the help of satellites, scientists began to better understand the specific source of this light pollution.
In the 2020 study led by Christopher Kyba of the German Earth Science Research Center, scientists performed experiments on Tucson's lamps. They brightened, then dimmed some street lights for a few nights, and used satellite images to observe the changes in Tucson's radiation. The result is not what you expected.
Kyba and colleagues found that after midnight, street lights accounted for only 13% of the city's visible light. If the city does not dim the lights, this number will rise to 18%. This means that most of the light comes from other types of artificial lighting.