# Proposed energy-metabolisms cannot explain the atmospheric chemistry of Venus Source: [Proposed energy-metabolisms cannot explain the atmospheric chemistry of Venus]() Collection index: [llms.txt]() Data updated: 2025-10-25T03:32:09.994Z Authors: Sean Jordan, Oliver Shorttle, Paul B. Rimmer Published: 2022-06-13T18:47:46.000Z ## Abstract Life in the clouds of Venus, if present in sufficiently high abundance, must be affecting the atmospheric chemistry. It has been proposed that abundant Venusian life could obtain energy from its environment using three possible sulfur energy-metabolisms. These metabolisms raise the possibility of Venus's enigmatic cloud-layer SO$\_2$-depletion being caused by life. We here couple each proposed energy-metabolism to a photochemical-kinetics code and self-consistently predict the composition of Venus's atmosphere under the scenario that life produces the observed SO$\_2$-depletion. Using this photo-bio-chemical kinetics code, we show that all three metabolisms can produce SO$\_2$-depletions, but do so by violating other observational constraints on Venus's atmospheric chemistry. We calculate the maximum possible biomass density of sulfur-metabolising life in the clouds, before violating observational constraints, to be $\\sim10^{-5}\\,-\\,10^{-3}\\,{\\rm mg\\,m^{-3}}$. The methods employed are equally applicable to aerial biospheres on Venus-like exoplanets, planets that are optimally poised for atmospheric characterisation in the near future. ## Recorded benchmark results A research result applies to its stated dataset, split, metric and evaluation configuration. Compare like-for-like settings, preserve the metric's unit and direction, and distinguish paper-reported results from independent reproduction. The best result recorded here is not a claim of exhaustive, current global coverage. ## Original sources and implementation [Original paper]() [PDF]()