The Dynamics of Stellar Coronae Harboring Hot-jupiters II. A Space Weather Event on A Hot-jupiter

TL;DR

This study uses numerical simulations to analyze how a Coronal Mass Ejection impacts a close-in giant exoplanet's magnetosphere, revealing strong shielding effects and significant energy deposition during space weather events.

Contribution

It introduces a detailed simulation of CME interactions with a hot Jupiter's magnetosphere, including planetary motion and unique magnetotail formation, highlighting differences from Earth's space weather responses.

Findings

Planet is well-shielded from CME penetration.

Energy deposition in magnetosphere is much higher than Earth's.

Large-scale change in magnetosphere-ionosphere current system during CME.

Abstract

We carry out a numerical simulation depicting the effects of a Coronal Mass Ejection (CME) event on a close-in giant planet in an extrasolar system. We drive the CME in a similar manner as in simulations of space weather events on Earth. The simulation includes the planetary orbital motion, which leads to the forming of a comet-like planetary magnetotail which is oriented almost perpendicular to the direction of propagation of the CME. The combination of this feature and the fact that the CME does not expand much by the time it reaches the planet leads to a unique CME-magnetosphere interaction, where the CME itself is highly affected by the presence of the planetary magnetosphere. We find that the planet is well-shielded from CME penetration, even for a relatively weak internal magnetic field. The planetary angular momentum loss associated with such an event is negligible compared to the total planetary angular momentum. We also find that the energy which is deposited in the magnetosphere is much higher than in the case of the Earth, and our simulation suggests there is a large-scale change in the orientation of the magnetosphere-ionosphere current system during the CME event.