Unraveling the Multi-Scale Solar Wind Structure Between Lagrange 1-point, Lunar Orbit and Earth’s Bow Shock: Better Space Weather Prediction Through Information Theory

The space weather effects at the Earth’s magnetosphere are mostly driven by the solar wind that carries the Interplanetary Magnetic Field (IMF). The incoming solar wind properties at L1 are typically used for developing various space weather forecasts. In this presentation we use several years of data in the solar wind from lunar orbiting ARTEMIS spacecraft and MMS upstream Earth’s bow shock to study the multi-scale structure of the IMF as determined by the Wavelet analysis. We determine the lag times between different scales and their dependence on 1) solar wind plasma properties and 2) spacecraft positions. Many solar wind parameters are correlated and anticorrelated with one another. We test the concept of conditional mutual information to isolate the effect of a single parameter and the dependence of various solar wind parameters on the time lags to provide the best/worse correlations between different scales. This will aid in isolating solar wind conditions when single point measurements of the IMF at Lagrange 1 point will likely lead to compromised space weather prediction accuracy

The Link Between Shocks, Turbulence and Magnetic Reconnection in Collisionless Plasmas

Global hybrid (electron fluid, kinetic ions) and fully kinetic simulations of the magnetosphere have been used to show surprising interconnection between shocks, turbulence and magnetic reconnection. In particular collisionless shocks with their reflected ions that can get upstream before retransmission can generate previously unforeseen phenomena in the post shocked flows: (i) formation of reconnecting current sheets and magnetic islands with sizes up to tens of ion inertial length. (ii) Generation of large scale low frequency electromagnetic waves that are compressed and amplified as they cross the shock. These \u27wavefronts\u27 maintain their integrity for tens of ion cyclotron times but eventually disrupt and dissipate their energy. (iii) Rippling of the shock front, which can in turn lead to formation of fast collimated jets extending to hundreds of ion inertial lengths downstream of the shock. The jets, which have high dynamical pressure, \u27stir\u27 the downstream region, creating large scale disturbances such as vortices, sunward flows, and can trigger flux ropes along the magnetopause. This phenomenology closes the loop between shocks, turbulence and magnetic reconnection in ways previously unrealized. These interconnections appear generic for the collisionless plasmas typical of space, and are expected even at planar shocks, although they will also occur at curved shocks as occur at planets or around ejecta

The Link Between Shocks, Turbulence and Magnetic Reconnection in Collisionless Plasmas

Global hybrid (electron fluid, kinetic ions) and fully kinetic simulations of the magnetosphere have been used to show surprising interconnection between shocks, turbulence and magnetic reconnection. In particular collisionless shocks with their reflected ions that can get upstream before retransmission can generate previously unforeseen phenomena in the post shocked flows: (i) formation of reconnecting current sheets and magnetic islands with sizes up to tens of ion inertial length. (ii) Generation of large scale low frequency electromagnetic waves that are compressed and amplified as they cross the shock. These \u27wavefronts\u27 maintain their integrity for tens of ion cyclotron times but eventually disrupt and dissipate their energy. (iii) Rippling of the shock front, which can in turn lead to formation of fast collimated jets extending to hundreds of ion inertial lengths downstream of the shock. The jets, which have high dynamical pressure, \u27stir\u27 the downstream region, creating large scale disturbances such as vortices, sunward flows, and can trigger flux ropes along the magnetopause. This phenomenology closes the loop between shocks, turbulence and magnetic reconnection in ways previously unrealized. These interconnections appear generic for the collisionless plasmas typical of space, and are expected even at planar shocks, although they will also occur at curved shocks as occur at planets or around ejecta