Much of our understanding of collisionless shocks comes from studies of the terrestrial bow shock upstream of the magnetosphere, which serves to slow down and thermalize the incident supersonic and super-Alfvenic plasma in the solar wind. Over the last decades, multi-spacecraft observations and computer simulations have helped to enhance our understanding of the physical process involved, and progress is still being made. In particular, 3D simulations of the shock front are now becoming feasible, something which will allow full spatial and temporal investigations of the shock processes. Some of the problems that yet remain unresolved are for example how the highly energetic field-aligned beams observed in the quasi-parallel section of the bow shock (i.e. where the shock normal is within 45 degrees of the upstream magnetic field) gain their initial energies, and the possible non-stationary features and reformation of the quasi-perpendicular shock front (i.e. where the angle between the shock normal and the upstream magnetic field exceeds 45 degrees) which has earlier been considered as a stable boundary.
Below is a short summary of four papers published within the last year that investigate several such issues, and which are all directly relevant to the work conducted within the SHOCK project.
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