Light batter for fish

A couple look up at the night sky where Orion’s belt is light batter for fish seen. But for myriad writers and artists, that source of inspiration could be fading as research has revealed light pollution is rapidly reducing the number of stars visible to the naked eye.

The study, published in the journal Science, suggests locations with 250 visible stars at present will have just 100 visible stars in 18 years. If these trends continue, eventually it will be very difficult to see anything at all in the sky, even the brightest constellations. Dr Christopher Kyba, of the German Research Centre for Geoscience and first author of the research. The team write that the glow produced by artificial lighting grew exponentially over the 20th century with population growth, new technologies, and expansion of towns and cities.

Satellites that can measure skyglow have limited resolution and cannot detect some wavelengths of light emitted by LEDs. To delve deeper, the team analysed 51,351 citizen scientist observations of stars visible to the naked eye, made between 2011 and 2022 as part of a project called Globe at Night. While the citizen science observations were rarely made multiple times in the exact same location, the researchers were able to group those with similar brightness of the night sky in a given year, and record the change over time. In 2016, scientists found the Milky Way was no longer visible to one-third of humanity. Europe and slightly higher, at 10.

Privacy Notice: Newsletters may contain info about charities, online ads, and content funded by outside parties. For more information see our Privacy Policy. The study has limitations, including that observations were largely made in Europe and the US, and in inhabited areas. Kyba noted the night sky in developing countries may be brightening even more rapidly than the global average suggested by the new study because they are electrifying for the first time. The study is not the first to reveal the impact of light pollution on our ability to see the night sky. Kyba said the results shine light on the money and energy wasted in night lighting, which also has environmental impacts.