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The accurate and timely prediction of solar eruptions is important for many space weather prediction tools and the Solar Orbiter mission. The aim of this study is to propose a new technique for the automated prediction of magnetic flux rope ejections in data driven NLFFF simulations hours in advance. We use a data-driven NLFFF model to describe the evolution of the 3D magnetic field of 8 active regions: 5 that produced an eruption and 3 where no eruption was observed. From the 3D magnetic field configuration, we determine a possible proxy for the loss of equilibrium of the magnetic flux rope based on the Lorentz force. Such proxy is significantly higher for the simulations of the eruptive active regions. For some cases, using a subset of the observed magnetograms, we ran a series of predictive simulations to test whether the time evolution of the proxy project forward in time can be used to predict the eruptions. We find that the identified proxy is useful in anticipating the magnetic flux rope ejection and that a meaningful prediction can be made up to 10 hours in advance. Although a number of issues need to be addressed for a fully operational application, this study presents an interesting solution for the prediction of CME onsets and future studies will address how to generalise the model such that it can be used.

The interaction of the shock waves originated from supernova explosions with the circumstellar medium provides crucial information on the physics of shock heating. Astrophysical shocks at all scales, from those in the heliosphere up to the cosmological shock waves, are typically collisionless and electrons, protons, and ions are expected to be heated at different temperatures. Although optical observations of Balmer-dominated shocks in young SNRs showed that the post-shock proton temperature is higher than the electron temperature, the actual dependence of the post-shock temperature on the particle mass is still widely debated. We tackle this longstanding issue through the analysis of deep multi-epoch and high-resolution observations of SN 1987A, made with the Chandra X-ray telescope. We study the observed spectra in close comparison with a dedicated full 3-D hydrodynamic simulation. The simulation is able to reproduce self-consistently the whole broadening of the spectral lines of many ions altogether. We could therefore measure the post shock temperature of protons and selected ions in the shocked circumstellar medium. We found that the ion to proton temperature ratio is always significantly higher than one and increases linearly with the ion mass for a wide range of masses and shock parameters. This provides information about the heating processes in collisionless shocks.