The Concept of Life on Venus Informs the Concept of Habitability
Abstract
An enduring question in astrobiology is how we assess extraterrestrial environments as being suitable for life. We suggest that the most reliable assessments of the habitability of extraterrestrial environments are made with respect to the empirically determined limits to known life. We discuss qualitatively distinct categories of habitability: empirical habitability that is constrained by the observed limits to biological activity; habitability sensu stricto, which is defined with reference to the known or unknown limits to the activity of all known organisms; and habitability sensu lato (habitability in the broadest sense), which is circumscribed by the limit of all possible life in the universe, which is the most difficult (and perhaps impossible) to determine. We use the cloud deck of Venus, which is temperate but incompatible with known life, as an example to elaborate and hypothesize on these limits.
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Associate Editor: Christopher P. McKay
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Copyright 2024, Mary Ann Liebert, Inc., publishers.
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Published online: 22 June 2024
Published in print: June 2024
Published ahead of print: 27 May 2024
Accepted: 2 May 2024
Received: 24 March 2024
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The authors declare they do not have a conflict of interest.
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This work was funded through the Science and Technology Facilities Council (STFC), grant ST/V000586/1.
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