Venusian Phosphine: A 'Wow!' Signal In Chemistry?


An overview of canonical processes that could in principle produce PH3 on Venus. None of the examined processes produce sufficient amounts of PH3 to explain the observed 1 ppb abundance (see (Bains et al., 2021 a) for the detailed analysis).

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.

William Bains, Janusz J. Petkowski, Sara Seager, Sukrit Ranjan, Clara Sousa-Silva, Paul B. Rimmer, Zhuchang Zhan, Jane S. Greaves, Anita M. S. Richards

Comments: A 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
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Instrumentation and Methods for Astrophysics (astro-ph.IM)
Journal reference: GPSS
DOI: 10.1080/10426507.2021.1998051
Cite as: arXiv:2111.05182 [astro-ph.EP] (or arXiv:2111.05182v1 [astro-ph.EP] for this version)
Submission history
From: Janusz Petkowski
[v1] Tue, 9 Nov 2021 14:48:12 UTC (692 KB)
https://arxiv.org/abs/2111.05182
Astrobiology, astrochemistry,

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