Habitability of Exoplanet Waterworlds

  title={Habitability of Exoplanet Waterworlds},
  author={Edwin Stephen Kite and Eric B. Ford},
  journal={The Astrophysical Journal},
  • E. Kite, E. Ford
  • Published 2 January 2018
  • Physics
  • The Astrophysical Journal
We model the evolution of ocean temperature and chemistry for rocky exoplanets with 10-1000$\times$ Earth's H$_2$O but without H$_2$, taking into account C partitioning, high-pressure ice phases, and atmosphere-lithosphere exchange. Within our model, for Sunlike stars, we find that: (1) habitability is strongly affected by ocean chemistry; (2) possible ocean pH spans a wide range; (3) exsolution-driven climate instabilities are possible; (4) surprisingly, many waterworlds stay habitable for… 
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