Presentation Archive

The SMILE mission: Global imaging of solar-terrestrial interactions

Graziella Branduardi-Raymont (MSSL-UCL)

January 31, 2022

Abstract: The solar wind coupling with the terrestrial magnetosphere is a key link in Sun-Earth interactions. Mass and energy enter geospace mainly via dayside magnetic reconnection under southward Interplanetary Magnetic Field conditions; reconnection in the geomagnetic tail leads to release of energy and particle injection deep into the magnetosphere, causing geomagnetic storms and substorms. One end product is the visual manifestation of variable auroral emissions. In-situ missions can provide detailed observations of the plasma and magnetic field conditions in both the solar wind and the magnetosphere. However, we are still unable to fully quantify the global effects of the drivers of Sun-Earth connections, and to monitor their evolution with time. This information is essential to develop a comprehensive understanding of how the Sun controls the Earth’s plasma environment and space weather. SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) offers a new approach to global monitoring of geospace by imaging the magnetosheath and cusps in soft X-rays emitted via the process of Solar Wind Charge eXchange (SWCX), when high charge-state solar wind ions exchange charges with exospheric neutrals. Moreover, SMILE is a self-standing mission coupling X-ray imaging of the magnetosheath and polar cusps (large spatial scales in the magnetosphere) with simultaneous UV imaging of global auroral distributions (mesoscale structures in the ionosphere) and in-situ solar wind/magnetosheath plasma and magnetic field measurements. SMILE will provide scientific data on the solar wind-magnetosphere interaction continuously for long, uninterrupted periods of time from a highly elliptical northern polar orbit. SMILE is a collaborative mission between ESA and the Chinese Academy of Sciences, currently under development and due for launch at the end of 2024. The novel science that SMILE will deliver, the ongoing technical developments and scientific preparations, and the current status of the mission, will be presented.