Plasma Observatory ESA M7 candidate mission: science and numerical support

Plasma Observatory (PO) multi‐scale space mission is one of the five ESA M7 candidates for a launch in 2037 and is currently undergoing a competitive Phase 0 at ESA, for further downselection to Phase A at the end of 2023. The mission concept is tailored to study plasma energization and energy transport in the Earth's Magnetospheric System, simultaneously at both fluid and ion scales, at which the largest amount of electromagnetic energy is converted into energized particles and energy is transported. PO targets the two ESA Voyage 2050 themes for ESA-led M Mission: Magnetospheric Systems and Plasma Cross-scale Coupling. Baseline mission includes one mothercraft and six identical smallsat daughtercraft, covering all the key regions of the Magnetospheric System. Plasma energization and energy transport are central in space plasma physics research, with important implications for space weather science as well as for the understanding of distant astrophysical plasmas, and are strictly interconnected with important processes such as shocks, magnetic reconnection, turbulence and waves, plasma jets and their combination. The Earth's Magnetospheric System is the complex and highly dynamic plasma environment where the strongest particle energization and energy transport occur in the near‐Earth space. PO Numerical Simulation Working Group (NSWG) provides support to the development of the mission concept during all phases of mission design, not only from the scientific point of view but also for the definition of the payload, as well as for the optimization of the configuration of the spacecraft constellation. Here, we discuss the concept of the PO space mission and the role of the NSWG, focusing specifically on the complex interaction between shocks and plasma turbulence and presenting a novel combination of magnetohydrodynamic (MHD) and small‐scale, hybrid kinetic simulations, where a shock is propagating in a turbulent medium. Finally, we put our modelling effort in the context of spacecraft observations, elucidating the role of cross‐scale, multi‐spacecraft simultaneous measurements in resolving shock front irregularities at different scales.