Abstract The art-science collaboration BioQuantum Record aims to bridge scientific inquiry and artistic narrative using an astrobiological lens to explore fundamental questions regarding life, otherness, and the human perspective. We propose to move away from an anthropocentric view and send extremophilic archaea, "microbial astronauts", to potentially establish first contact with extra-terrestrial microorganisms. This parallels the search for life in astrobiology, which mainly focuses on the search for microbial life. This transdisciplinary approach merges art and science by maintaining a liminal state of uncertainty and openness to new forms of knowledge. We derived experimental methodological approaches from anthropological concepts to support a research stance in which the artist acts as a catalytic figure, enabling a transdisciplinary practice that unfolds collaboratively and opens new avenues for exploring anthropological concepts in art-science collaborations. This culminated in an art-science performance and exhibition that fused scientific protocols with artistic exploration to create science-fiction-inspired encounters. We conclude that astrobiology can be used as a means to explore otherness, with transdisciplinarity creating a shared space for encountering uncertainty and generating new inquiries.