Cross-scale: multi-scale coupling in space plasmas

Abstract

International audienceMost of the visible universe is in the highly ionised plasma state, and most of that plasma is collision-free. Three physical phenomena are responsible for nearly all of the processes that accelerate particles, transport material and energy, and mediate flows in systems as diverse as radio galaxy jets and supernovae explosions through to solar flares and planetary magnetospheres. These processes in turn result from the coupling amongst phenomena at macroscopic fluid scales, smaller ion scales, and down to electron scales. Cross-Scale, in concert with its sister mission SCOPE (to be provided by the Japan Aerospace Exploration Agency—JAXA), is dedicated to quantifying that nonlinear, time-varying coupling via the simultaneous in-situ observations of space plasmas performed by a fleet of 12 spacecraft in near-Earth orbit. Cross-Scale has been selected for the Assessment Phase of Cosmic Vision by the European Space Agency

The Scientific Foundations of Forecasting Magnetospheric Space Weather

“…Nevertheless, the measurements are sparse, and this represents a major obstacle to progress in magnetospheric physics as a whole. So-called constellation missions represent an obvious next step forward and an intriguing possibility is to use CubeSat platforms (Spence et al 2001(Spence et al , 2004Schwartz et al 2009;Eastwood 2015). This would be complemented by missions that exploit remote sense.…”

Current state and perspectives of Space Weather science in Italy

“…Notably, the remarkable discoveries and the lessons collected during the last two decades of in situ observations have also highlighted the strong need for new measurements in terms of enhanced time and phase resolution of particles detection (Vaivads et al, 2016) and/or of multiple point, multi-scale plasma observations in the near-Earth space (e.g., Schwartz et al, 2009). A substantial leap forward would be driven by such observations in our comprehension on how energy is processed by fundamental plasma processes, like turbulence and shocks, and how particle are energized in space plasmas, enabling progresses in many Space Weather topics.…”

Microphysics in Astrophysical Plasmas

“…All dynamical media involve disparate scales which couple to one another (Schwartz et al 2009a(Schwartz et al , 2009b. In viscous fluids, the thin boundary layers are driven by, and strongly influence, the macroscopic flow field.…”