Abstract | Turbulence is ubiquitous in astrophysical plasmas. It is thought to play a major role in accretion flows around compact objects (e.g., black holes), star formation in the ISM, solar corona heating and solar wind (SW) acceleration. In planetary magnetospheres, turbulence enhances particle energization in various key regions (cusp, magnetotail, …) and impacts SW particle entry through magnetic reconnection at the magnetopause.
Here we review some results obtained using on Messenger data on characterizing plasma turbulence in various regions of the Hermean environment, both at large (MHD) scales and sub-ion (kinetic) scales. This includes the compressible vs. incompressible nature of the turbulence, their spectral properties and the role of ion-scale instabilities. We will confront the results to previous ones obtained in the SW and other planetary magnetospheres. A focus will be put on the range of scales where the 1/f spectrum is observed. We provide solid theoretical and observational evidence of the role of magnetic reconnection in driving sub-ion scale turbulence even in the absence of a fully developed turbulence in the inertial (MHD) range. Prospects on using the upcoming data from the BepiColombo missions in completing and extending these studies will be discussed.
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