2025RNAAS...9..343M

In this note I present a Bayesian analysis of the probability of abiogenesis in light of recent measurements by the James Webb Space Telescope of dimethyl sulfide and dimethyl disulfide in K2-18b's atmosphere. I explore how the discovery of a second instance of life beyond Earth would affect the posterior distribution of the rate of abiogenesis λ. Building on the work of D. S. Spiegel & E. L. Turner and D. Kipping, it is no surprise that including the hypothetical K2-18b datum constrains small values of λ, implying that abiogenesis may not be exceedingly rare. However, under the objective prior assumption of D. Kipping, the Earth datum is already strongly constraining λ's posterior distribution and an additional datum does not alter D. Kipping's conclusions.