Atmospheric Evolution on Low-gravity Waterworlds

  title={Atmospheric Evolution on Low-gravity Waterworlds},
  author={Constantin W. Arnscheidt and Robin D. Wordsworth and Feng Ding},
  journal={The Astrophysical Journal},
Low-gravity waterworlds ($M\lesssim 0.1 M_{\oplus}$) are of interest for their potential habitability. The weakly bound atmospheres of such worlds have proportionally larger radiative surfaces and are more susceptible to escape. We conduct a unified investigation into these phenomena, combining analytical energy balance and hydrodynamic escape with line-by-line radiative transfer calculations. Because outgoing radiation is forced to increase with surface temperature by the expansion of the… 

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