Stellar Wind -- Magnetosphere Interactions in Hot Jupiters

TL;DR

This paper models how stellar wind and magnetosphere interactions can generate currents that heat hot Jupiters, potentially explaining their inflated radii and offering observable signatures.

Contribution

It provides a detailed model of star-planet magnetic interactions, expanding on earlier results to assess their significance and observational implications.

Findings

Currents from stellar wind-magnetosphere interactions can significantly heat hot Jupiters.

The model predicts observable signatures of these interactions.

Conditions under which this heating is most effective are identified.

Abstract

One potential star-planet interaction mechanism for hot Jupiters involves planetary heating via currents set up by interactions between the stellar wind and planetary magnetosphere. Early modeling results indicate that such currents, which are analogous to the terrestrial global electric circuit (GEC), have the potential to provide sufficient heating to account for the additional radius inflation seen in some hot Jupiters. Here we present a more detailed model of this phenomenon, exploring the scale of the effect, the circumstances under which it is likely to be significant, implications for the planetary magnetospheric structure, and observational signatures.