Planetary Protection & Biosafety

Rethinking Planetary Protection: An Island Biogeographical Analysis

By Keith Cowing

Status Report

Journal of the Royal Society

June 30, 2025

Filed under Away Team, Biosafety, contamination, island biogeography, Journal of the Royal Society, microbiology, planetary protection

Rethinking Planetary Protection: An Island Biogeographical Analysis — On November 14, 1963, an Icelandic fisherman noticed a plume of smoke rising from the open water. Within a day, Surtsey, a new volcanic island, had formed off the southern coast of Iceland This image was acquired on June 12, 2001, by Space Imaging’s IKONOS satellite. The data are archived by the NASA Scientific Data Purchase. Source

We reconsider the problem of planetary protection using, by the analogy of planets as islands, the theory of island biogeography.

We show that although the notion of equilibrium populations that emerge from the effects of immigration and extinction generally breaks down when applied to interplanetary scales, the mean-time to extinction resulting from the combined effects of growth and death rates can be quantified.

We reconsider the probabilistic model of planetary protection, discuss how mean-time to extinction can instead be used to assess contamination risk, and we propose a research direction for planetary protection based on these ideas.

We discuss more broadly the applicability of island biogeography to considering biotic transfer at interplanetary scales.

Rethinking planetary protection: an island biogeographical analysis, Journal of the Royal Society (open access)

Astrobiology, Planetary Protection,

Keith Cowing

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻

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