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dc.contributor.authorSeager, Sara
dc.contributor.authorBains, William
dc.contributor.authorHu, Rui
dc.date.accessioned2014-03-10T21:16:15Z
dc.date.available2014-03-10T21:16:15Z
dc.date.issued2013-09
dc.date.submitted2012-10
dc.identifier.issn0004-637X
dc.identifier.issn1538-4357
dc.identifier.urihttp://hdl.handle.net/1721.1/85605
dc.descriptionAuthor Manuscript September 24, 2013en_US
dc.description.abstractBiosignature gas detection is one of the ultimate future goals for exoplanet atmosphere studies. We have created a framework for linking biosignature gas detectability to biomass estimates, including atmospheric photochemistry and biological thermodynamics. The new framework is intended to liberate predictive atmosphere models from requiring fixed, Earth-like biosignature gas source fluxes. New biosignature gases can be considered with a check that the biomass estimate is physically plausible. We have validated the models on terrestrial production of NO, H[subscript 2]S, CH[subscript 4], CH[subscript 3]Cl, and DMS. We have applied the models to propose NH[subscript 3] as a biosignature gas on a "cold Haber World," a planet with a N[subscript 2]-H[subscript 2] atmosphere, and to demonstrate why gases such as CH[subscript 3]Cl must have too large of a biomass to be a plausible biosignature gas on planets with Earth or early-Earth-like atmospheres orbiting a Sun-like star. To construct the biomass models, we developed a functional classification of biosignature gases, and found that gases (such as CH[subscript 4], H[subscript 2]S, and N[subscript 2]O) produced from life that extracts energy from chemical potential energy gradients will always have false positives because geochemistry has the same gases to work with as life does, and gases (such as DMS and CH[subscript 3]Cl) produced for secondary metabolic reasons are far less likely to have false positives but because of their highly specialized origin are more likely to be produced in small quantities. The biomass model estimates are valid to one or two orders of magnitude; the goal is an independent approach to testing whether a biosignature gas is plausible rather than a precise quantification of atmospheric biosignature gases and their corresponding biomasses.en_US
dc.description.sponsorshipFoundational Questions Institute (FQXi)en_US
dc.language.isoen_US
dc.publisherIOP Publishingen_US
dc.relation.isversionofhttp://dx.doi.org/10.1088/0004-637x/775/2/104en_US
dc.rightsCreative Commons Attribution-Noncommercial-Share Alikeen_US
dc.rights.urihttp://creativecommons.org/licenses/by-nc-sa/4.0/en_US
dc.sourcearXiven_US
dc.titleA BIOMASS-BASED MODEL TO ESTIMATE THE PLAUSIBILITY OF EXOPLANET BIOSIGNATURE GASESen_US
dc.typeArticleen_US
dc.identifier.citationSeager, S., W. Bains, and R. Hu. “A BIOMASS-BASED MODEL TO ESTIMATE THE PLAUSIBILITY OF EXOPLANET BIOSIGNATURE GASES.” The Astrophysical Journal 775, no. 2 (October 1, 2013): 104.en_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciencesen_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Physicsen_US
dc.contributor.mitauthorSeager, Saraen_US
dc.contributor.mitauthorBains, Williamen_US
dc.contributor.mitauthorHu, Ruien_US
dc.relation.journalThe Astrophysical Journalen_US
dc.eprint.versionAuthor's final manuscripten_US
dc.type.urihttp://purl.org/eprint/type/JournalArticleen_US
eprint.statushttp://purl.org/eprint/status/PeerRevieweden_US
dspace.orderedauthorsSeager, S.; Bains, W.; Hu, R.en_US
dc.identifier.orcidhttps://orcid.org/0000-0002-6892-6948
mit.licenseOPEN_ACCESS_POLICYen_US
mit.metadata.statusComplete


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