Main-sequence exoplanet systems: tidal evolution

TL;DR

This paper reviews how tidal interactions influence the orbital evolution, physical characteristics, and ultimate fate of close-in exoplanets, highlighting their significance in shaping observed exoplanet populations.

Contribution

It provides an overview of tidal physics and discusses their observable effects on the properties and distribution of close-in exoplanets.

Findings

Tides significantly affect exoplanet orbital dynamics.

Tidal heating can cause planetary radius expansion.

Tides may lead to planetary spiral-in and destruction.

Abstract

The easiest exoplanets to detect are those that orbit very close to their hoststars. As a result, even though these planets are quite rare, they represent amajor fraction of the current exoplanet population. A side-effect of theproximity between the planet and the star is that the two have strong mutualinteractions through a number of physical processes. One of the most importantof these processes is tides. Tides are thought to shape the orbits of close-inexoplanets, heat the planet making its radius expand, and even drive someplanets to spiral into their host stars. This chapter briefly introduces thebasics of tidal physics and describes the various fingerprints tides leavewithin the observed exoplanet population.