A Volcanic Hydrogen Habitable Zone

  title={A Volcanic Hydrogen Habitable Zone},
  author={Ramses Mario Ramirez and Lisa Kaltenegger},
  journal={The Astrophysical Journal Letters},
  • R. RamirezL. Kaltenegger
  • Published 27 February 2017
  • Geology, Physics, Environmental Science
  • The Astrophysical Journal Letters
The classical habitable zone (HZ) is the circular region around a star in which liquid water could exist on the surface of a rocky planet. The outer edge of the traditional N2–CO2–H2O HZ extends out to nearly ∼1.7 au in our solar system, beyond which condensation and scattering by CO2 outstrips its greenhouse capacity. Here, we show that volcanic outgassing of atmospheric H2 can extend the outer edge of the HZ to ∼2.4 au in our solar system. This wider volcanic-hydrogen HZ (N2–CO2–H2O–H2) can… 

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