The plasma environment of near-Earth space requires continuous monitoring, as its dynamics can affect modern technology in various ways, sometimes leading to significant economic losses. At the same time, it gives rise to spectacular phenomena such as aurora. In this talk, I will discuss a magnetospheric process responsible for generating auroral spirals, which also acts as a powerful particle accelerator. Energetic charged particles at hundreds of keV are a known source of lost observation time in astrophysical X-ray missions such as XMM-Newton, and pose a threat to future missions including SMILE and NewAthena. To mitigate such costly impacts, we developed machine learning models of the energetic particle population based on Cluster mission observations. Beyond these technological consequences, the precipitation of energetic particles influences atmospheric escape through ionospheric ion outflow. Our cold ion outflow model, also based on Cluster data, can be used to scale the effects of stellar wind–magnetosphere interaction to Earth-like exoplanets — bridging space physics with exoplanetary science