The Steppenwolf: A proposal for a habitable planet in interstellar space
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.
Cite
@article{arxiv.1102.1108,
title = {The Steppenwolf: A proposal for a habitable planet in interstellar space},
author = {Dorian S. Abbot and Eric R. Switzer},
journal= {arXiv preprint arXiv:1102.1108},
year = {2015}
}
Comments
4 pages, 1 figure, updated to match accepted version