Laboratory and computer simulations of the global magnetosheric effects caused by anti-asteroidal explosions at near-Earth space Original Research Article

Up today the only probable scenario to mitigate a collision with new Near-Earth Objects of 1km-size consists of theirs deflection by a very high-energy explosion (100–1000 MT of TNT) at the distances from the Earth comparable with the sun-ward scale of magnetosphere. Since magnetosphere own magnetic energy is not more than 250MT, it means that a giant plasma cloud (of energy ∼100MT) released by such explosion may cause global and even catastrophic geoplasma disturbances. The magnitude and nature of them canʹt be predicted by existing 3D numerical codes in a full measure. The necessary data about the after-effects can be obtained mainly in simulation experiments on expansion of Laser-produced Plasma Clouds inside of laboratory model of magnetosphere. Since in case of near-Earth explosion plasma expansion will be sub-Alfvenic, as the first step the dynamic of plasma clouds in a vacuum dipole magnetic field have been studied experimentally1 and the results obtained have been compared with MHD analytical model3 and 3D/PIC-numerical simulation2. A preliminary analysis shows that initial evolution of plasma clouds can be satisfactorily described by MHD-based similarity criterion and scales.