Energetic Electron Observations During BepiColombo’s First Three Mercury Flybys

Mercury hosts a dynamic and highly variable magnetosphere shaped by its weak intrinsic magnetic field and the intense pressure of the solar wind. Previous observations from spacecraft sent to the planet have provided key insights into Mercury’s magnetospheric structure and energetic particle populations, revealing transient and highly variable energetic electron enhancements within the planet’s magnetosphere. We present BepiColombo/SIXS observations of energetic electron populations in Mercury’s magnetosphere during the spacecraft’s first three flybys of the planet. Although no such populations were observed during the first flyby, strong energetic electron signatures were observed during the second and third flybys. These observations are discussed in the context of observations by MESSENGER (Lawrence et al., 2015) in the invariant latitude-MLT plane, showing good agreement between the two data sets. Additionally, we present the highest time resolution energy spectra (> 70 keV) produced at Mercury during the second and third flybys.