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"La nuit est belle 2023 !"

Poster of "La nuit est belle 2023"


On the evening of Friday, 22 September, CERN will be participating in the 4th edition of “La nuit est belle” event, during which the street lighting of more than 150 communes in the local area will remain switched off.

This 4th edition will be dedicated to human beings and the night. Lighting influences our body and our habits: "La nuit est belle 2023!" questions two major topics: health and safety at night.

CERN will join this initiative by switching off the lights all evening and night, of the Globe, the Esplanade des Particules, Gates A, B, C and E, the roads and car parks on the Meyrin and Prévessin sites, and the SPS and LHC sites, as well as a public event organised by the CERN astronomy club.

If you are working at CERN, you can contribute by switching off your computers, monitors and lights when you go home. Please remember that switching off computers and lights is good practice in general to save energy and favour biodiversity at night, read more: https://hse.cern/content/energy-management.

Cyclists and pedestrians – make sure that you can be seen in the dark! Car-drivers – stay alert!
HSE recommends that you wear light-coloured clothing, preferably with reflectors, if you are out when it is dark:

  • People wearing dark clothes will be seen by a car from a distance of about 25 metres
  • People wearing light-coloured clothes will be seen from a distance of about 40 metres
  • People wearing reflectors will be seen from a distance of about 125 metres

During the evening, many activities will be organised in the local area:

  • Visit https://lanuitestbelle.org for more information and to register for activities
  • Follow the event live on social media via the hashtag #lanuitestbelle