The few studies that have been carried out on people's relationship with nocturnal space-time are limited, on the one hand, to the urban areas of the major northern cities and, on the other, to the acceptance of the technical responses currently prescribed by the top-down spheres of action in order to limit the negative externalities of artificial light at night, particularly from an energy and ecological point of view. By not moving away from the purely physical measurement of the fundamental parameters of lighting, this work makes no epistemological or methodological break with those who seek to define 'fair lighting' in terms of an exclusively quantitative, mechanistic and context-free relationship between the costs and benefits of the brightest light on the one hand and the densest darkness on the other.

The Outrenoir programme ('Participation des populations habitantes à la caractérisation des socio-écosystèmes nocturnes des territoires réunionnais' - 'Participation of the local population in the characterisation of the nocturnal socio-ecological systems of Reunion Island') takes the approach of looking for a new way of characterising nocturnal socio-ecological systems other than under street lights. In this approach, we take the gamble of decentering our gaze: it is no longer artificial light but the soundscape that becomes our point of entry into the debate on the challenges of preserving the nocturnal environment. The latter is interpreted here in a mesological perspective that goes beyond the tension between artificial light and natural darkness, as a relational and multisensory matrix. Acoustics provides a technical medium for exploring these relationships in participatory workshops involving local residents, researchers and staff from the Réunion National Park.