Rocky planet rotation, thermal tide resonances, and the influence of biological activity

TL;DR

This paper explores how atmospheric thermal tide resonances can significantly influence the rotational evolution of rocky planets, especially in the presence of biological activity like oxygenation, which may leave detectable biosignatures.

Contribution

It demonstrates that thermal tide resonances can stall planetary rotational evolution and suggests biological activity could impact this process, revealing a novel biosignature influence.

Findings

Thermal tide resonances can halt planetary spin evolution.

Biological oxygenation may affect atmospheric tides and rotation.

Potential biosignature linked to planetary rotation states.

Abstract

It has been established theoretically that atmospheric thermal tides on rocky planets can lead to significant modifications of rotational evolution, both close to synchronous rotation and at faster rotations if certain resonant conditions are met. Here it is demonstrated that the normally considered dissipative gravitational tidal evolution of rocky planet rotation could, in principle, be 'stalled' by thermal tide resonances for Earth-analog worlds in the liquid water orbital zone of stars more massive than ~0.3 Msolar. The possibility of feedback effects between a planetary biosphere and the planetary rotational evolution are examined. Building on earlier studies, it is suggested that atmospheric oxygenation, and ozone production could play a key role in planetary rotation evolution, and therefore represents a surprising but potent form of biological imprint on astronomically accessible planetary characteristics.