Astrobiological Potential of Venus Atmosphere Chemical Anomalies and Other Unexplained Cloud Properties

Abstract

Long-standing unexplained Venus atmosphere observations and chemical anomalies point to unknown chemistry but also leave room for the possibility of life. The unexplained observations include several gases out of thermodynamic equilibrium (e.g. tens of ppm O2, the possible presence of PH3 and NH3, SO2 and H2O vertical abundance profiles), an unknown composition of large, lower cloud particles, and the "unknown absorber(s)". Here we first review relevant properties of the Venus atmosphere and then describe the atmospheric chemical anomalies and how they motivate future astrobiology missions to Venus.

Published in Astrobiology (in press); Partially based on the text of the Venus Life Finder Mission Study report (arXiv:2112.05153)

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Cited by in corpus (5)

• Stability of nucleic acid bases in concentrated sulfuric acid: Implications for the habitability of Venus' clouds
• Venus' Atmospheric Chemistry and Cloud Characteristics Are Compatible with Venusian Life
• Simple lipids form stable higher-order structures in concentrated sulfuric acid
• Venus Cloud Research: Progress and Perspectives
• The effect of a biosphere on the habitable timespan of stagnant-lid planets and implications for the atmospheric spectrum