Street lamps, light signs and illuminated buildings - light at night means security and nicer cities, but has also been shown to have negative effects on people and animals. The more artificial lights, the fewer stars you can see in the night sky.
Counting stars for science
The "Stjärnförsöket" (the Star Spotting Experiment) project collects contributions about light pollution in Sweden and in partner countries. By pointing a cardboard tube in all cardinal directions, Citizen Scientists record how many stars they see at their current location. By these values, light pollution can be calculated directly in the Citizen Science app. How many stars can you see where you live? Wtih this app you can help scientists measure light pollution by counting stars in the sky!
The project is part of the "Forskar Fredag 2019" initiative, funded by the EU Horizon 2020 program.