Journal Article

The Comprehensive Response of the Magnetopause to the Impact of an Isolated Magnetosheath High‐Speed Jet

Gao, Xinliang, Wang, Chi, Liu, Huijie, Li, Wenya, Guo, Wenlong, Tang, Binbin, Guo, Jin, Lu, Quanming, Ma, Jiuqi

2024

Overview

The magnetopause is the boundary between the Earth's magnetosphere and the solar wind. Magnetosheath high‐speed jets can impact the magnetopause, causing local indentation and subsequently rebound. However, the comprehensive response of the magnetopause to the impact of a high‐speed jet remains unclear. In this study, we establish that the full spatiotemporal response pattern of the magnetopause to the impact of an isolated magnetosheath high‐speed jet can be characterized as an “Indentation‐Rebounce‐Relaxation” sequence from a statistical view. Based on the pressure balance, we estimate the spatial and temporal scales of the entire response process to range from 0.5 to 3.2 Earth radii and 0.9–4.7 min, respectively. Furthermore, we find that the interaction between the magnetopause and the high‐speed jet during the rebounce phase distorts the magnetopause, subsequently generating pairs of field‐aligned currents. These generated field‐aligned currents may flow to the ionosphere, potentially contributing to magnetosphere‐ionosphere coupling. Plain Language Summary The Earth's magnetopause, separating the Earth's magnetosphere from the solar wind, is usually distorted by upstream magnetosheath pressure perturbations. One of these is the magnetosheath high‐speed jets, which are localized dynamic pressure enhancements that can induce the local deformation of the magnetopause. Previous studies have found that magnetosheath high‐speed jets can interact with the magnetopause, causing local indentation and subsequent rebound. However, due to the limitations of in‐situ spacecraft observations, the complete response of the magnetopause to the impact of a high‐speed jet remains unknown. Using Magnetospheric Multiscale satellite data, we establish a comprehensive response pattern of the magnetopause to an HSJ for the first time based on the statistical analysis of multiple cases, which is described as a sequence of “Indentation‐Rebounce‐Relaxation”. This study will help us better understand the solar wind‐magnetosphere coupling process. Key Points The spatiotemporal response of the magnetopause to an isolated HSJ can be sequenced as ‘Indentation‐Rebounce‐Relaxation’ The estimated spatial and temporal scales of the magnetopause response range from 0.5 to 3.2 Earth radii and 0.9–4.7 min, respectively The high‐speed jet induces deformation of the magnetopause, subsequently generating pairs of field‐aligned currents

• Publisher: John Wiley & Sons, Inc,Wiley
• Subject: Deformation / Dynamic pressure / Earth / Earth magnetosphere / field‐aligned current / high‐speed jets / Impact analysis / Indentation / Ionosphere / Jets / Jupiter / Magnetopause / Magnetosheath / Magnetosphere-ionosphere coupling / Magnetospheric-solar wind relationships / Pattern analysis / Pressure / Satellite data / Satellite observation / Saturn / Solar wind / Spacecraft / Statistical analysis / Statistical methods / Statistics