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arXiv · 1803.08937

A New Desalination Pump Help Define the pH of Ocean Worlds

Amit Levi·Dimitar Sasselov
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Abstract

We study ocean exoplanets, for which the global surface ocean is separated from the rocky interior by a high-pressure ice mantle. We describe a mechanism that can pump salts out of the ocean, resulting in oceans of very low salinity. Here we focus on the H2O-NaCl system, though we discuss the application of this pump to other salts as well. We find our ocean worlds to be acidic, with a pH in the range of 2-4. We discuss and compare between the conditions found within our studied oceans and the conditions in which polyextremophiles were discovered. This work focuses on exoplanets in the super-Earth mass range (2 M_Earth), with water composing at least a few percent of their mass. Although, the principal of the desalination pump may extend beyond this mass range.

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Amit Levi, Dimitar Sasselov. 2018-03-23. A New Desalination Pump Help Define the pH of Ocean Worlds. https://doi.org/10.3847/1538-4357%2Faab715

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