LASP Magnetosphere Seminars

Abstract

Precursor solitons, predicted by theory to arise when a charged object moves through plasma above a critical velocity, are experimentally observed. These ion-acoustic solitons form ahead of the object and propagate faster than it, providing an early indication of its motion. Experiments were conducted in the Space Plasma Simulation Chamber (SPSC) at the Naval Research Laboratory, where biased rings and an axial magnetic field generated controlled plasma flows. A debris object was placed in the chamber such that the plasma streamed past it, leading to the regular excitation of precursor solitons traveling upstream against the flow. The ability to observe such solitons in space could enable a novel method for detecting and tracking small-scale debris in the Earth’s ionosphere and lower magnetosphere.