Phosphine as a Biosignature Gas in Exoplanet Atmospheres.

  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},
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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