Light pollution affects every region on Earth, including at the poles and even above us in low-Earth orbit. That isn’t news. But the extent of the problem, laid out in our Focus on dark skies, is startling and should turn us all into activists.
On 23 February 2023, Ynys Enlli in north Wales joined a growing list of geographically remote International Dark Sky Sanctuaries, which includes the Pitcairn Islands and !Ae!Hai Kalahari Heritage Park, South Africa. These sites must meet strict criteria for the quality of the night sky and are only designated after extensive monitoring.

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While each additional protected dark sky location is a win, we need to address the underlying causes that necessitate intervention in the first place. Our Focus on dark skies looks at just that. The authors not only point out the various problems — and