Astrobiological Potential of Venus Atmosphere Chemical Anomalies and Other Unexplained Cloud Properties
Janusz J. Petkowski, Sara Seager, David Grinspoon, William Bains, Sukrit Ranjan, Paul B. Rimmer, Weston P. Buchanan, Rachana Agrawal, Rakesh Mogul, Christopher E. Carr
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 O 2 , the possible presence of PH 3 and NH 3 , SO 2 and H 2 O vertical abundance profiles), an unknown composition of large, lower cloud particles, and the “unknown absorber(s).” Here we first review relevant properties of the venusian atmosphere and then describe the atmospheric chemical anomalies and how they motivate future astrobiology missions to Venus.