A Note on Planet Size and Cooling Rate

TL;DR

This paper discusses how smaller terrestrial planets cool more slowly than larger ones due to force balance variations, impacting their surface environments and implications for extraterrestrial life searches.

Contribution

It highlights the importance of considering small planets in astrobiology, challenging the bias towards larger planets in habitability studies.

Findings

Small planets cool slower than larger planets.

Interior cooling influences surface geological activity.

Small planets remain potentially habitable despite size.

Abstract

Variation in the balance of forces that drive and resist tectonic plate motions allows small terrestrial planet to cooler slower than larger ones. Given that interior cooling affects surface environment, through volcanic/geologic activity, this indicates that small planets should not be down-weighted in the search for life beyond Earth.