Valuing and representing exogeodiversity: From scientific imagery to artistic imagination

Geodiversity –i.e., the abiotic equivalent of biodiversity– has gained international recognition and usage for more than two decades in the field of geosciences. It now has the theoretical foundations and practical applications of a new paradigm underlying strategies of geoconservation. However, geodiversity has rarely been considered in the context of extraterrestrial environments despite the great geological and geomorphological diversities of celestial bodies revealed by planetary science missions for at least a mid-century. In this paper, we propose to introduce the term “exogeodiversity” to encompass the variety of geological, geomorphological, regolith and hydrological features on all extraterrestrial rocky bodies. Like its terrestrial counterpart, exogeodiversity is endowed with a range of societal values, including cultural, historic, artistic, aesthetic, functional, scientific and educational ones. Given the threats associated with the many projects of human exploration of planetary surfaces, an objective assessment of these values is more than ever required. In the absence of direct (in situ) observations with the notable exception of the Moon, the only (indirect) way for a valuation of exogeodiversity is provided by an analysis of the scientific and artistic representations whose historical trajectories are intimately cross-cut. Finally, we stress the potential of the images to promote exogeodiversity in the era of digital technologies, for instance by imagining new forms of virtual exogeotourism.