Phosphine as a Biosignature Gas in Exoplanet Atmospheres.

@article{SousaSilva2019PhosphineAA,
  title={Phosphine as a Biosignature Gas in Exoplanet Atmospheres.},
  author={Clara Sousa-Silva and Sara Seager and Sukrit Ranjan and Janusz Jurand Petkowski and Zhuchang Zhan and Renyu Hu and William Bains},
  journal={Astrobiology},
  year={2019}
}
A long-term goal of exoplanet studies is the identification and detection of biosignature gases. Beyond the most discussed biosignature gas O2, only a handful of gases have been considered in detail. In this study, we evaluate phosphine (PH3). On Earth, PH3 is associated with anaerobic ecosystems, and as such, it is a potential biosignature gas in anoxic exoplanets. We simulate the atmospheres of habitable terrestrial planets with CO2- and H2-dominated atmospheres and find that PH3 can… 
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Detecting biosignature gases on exoplanet atmosphere with near-future space telescopes is one of the most promising methods of detecting life beyond Earth. However, only a handful of biosignature g...
Upper limits for phosphine (PH3) in the atmosphere of Mars
Phosphine (PH3) is proposed to be a possible biomarker in planetary atmospheres and has been claimed to have been observed in the atmosphere of Venus, sparking interest in the habitability of Venus’s
Phosphine Generation Pathways on Rocky Planets.
TLDR
Corrosion of large impactors as they ablate near Venus' cloud layer, and the presence of reduced phosphorus compounds in the subcloud layer could result in production of phosphine and may explain the phosphine detected in Venus' atmosphere or on other rocky planets.
The case and context for atmospheric methane as an exoplanet biosignature
Significance Astronomers will soon begin searching for biosignatures, atmospheric gases or surface features produced by life, on potentially habitable planets. Since methane is the only biosignature
Phosphine on Venus Cannot Be Explained by Conventional Processes.
TLDR
This work thoroughly explores the potential pathways of formation of phosphine in a venusian environment, including in the planet's atmosphere, cloud and haze layers, surface, and subsurface, and provides a template for investigation of phosphines as a biosignature on other worlds.
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