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arXiv · 1102.1108

The Steppenwolf: A proposal for a habitable planet in interstellar space

Dorian S. Abbot·Eric R. Switzer
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Abstract

Rogue planets have been ejected from their planetary system. We investigate the possibility that a rogue planet could maintain a liquid ocean under layers of thermally-insulating water ice and frozen atmosphere as a result of geothermal heat flux. We find that a rogue planet of Earth-like composition and age could maintain a subglacial liquid ocean if it were ~3.5 times more massive than Earth. If a rogue planet had about ten times higher water mass fraction or a thick cryo-atmospheric layer, it would need to be only ~0.3 times the mass of Earth to maintain a liquid ocean. Such a planet could be detected from reflected solar radiation and its thermal emission could be characterized in the far-IR if it passed within O(1000) AU of Earth.

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Dorian S. Abbot, Eric R. Switzer. 2011-06-02. The Steppenwolf: A proposal for a habitable planet in interstellar space. https://doi.org/10.1088/2041-8205%2F735%2F2%2Fl27

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