Venusian phosphine: a 'Wow!' signal in chemistry?

Abstract

The potential detection of ppb levels phosphine (PH3) in the clouds of Venus through millimeter-wavelength astronomical observations is extremely surprising as PH3 is an unexpected component of an oxidized environment of Venus. A thorough analysis of potential sources suggests that no known process in the consensus model of Venus' atmosphere or geology could produce PH3 at anywhere near the observed abundance. Therefore, if the presence of PH3 in Venus' atmosphere is confirmed, it is highly likely to be the result of a process not previously considered plausible for Venusian conditions. The source of atmospheric PH3 could be unknown geo- or photochemistry, which would imply that the consensus on Venus' chemistry is significantly incomplete. An even more extreme possibility is that strictly aerial microbial biosphere produces PH3. This paper summarizes the Venusian PH3 discovery and the scientific debate that arose since the original candidate detection one year ago.

arXiv commentA short overview of the Venusian PH3 discovery and the scientific debate that arose since the original candidate detection in September 2020. Additional discussion of possible non-canonical sources of PH3 on Venus is also included. arXiv admin note: text overlap with arXiv:2009.06499

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Cited by in corpus (5)

• Low levels of sulphur dioxide contamination of Venusian phosphine spectra
• Venus' Atmospheric Chemistry and Cloud Characteristics Are Compatible with Venusian Life
• Astrobiological Potential of Venus Atmosphere Chemical Anomalies and Other Unexplained Cloud Properties
• Constraints on the production of phosphine by Venusian volcanoes
• Aerial Platform Design Options for a Life-Finding Mission at Venus