Computer experiments on electromagnetic disturbance produced by a spacecraft in a fast plasma flow

Abstract

AbstractWhen the electromagnetic environment of the space plasma is observed by a spacecraft in space, it is often difficult to distinguish the disturbance due to the satellite itself and natural phenomena. In such cases, it is effective to use a numerical experiment in which the phenomena arising around a spacecraft are reconstructed on a computer. Since the plasma filling the space is extremely dilute, the particles are in a collisionless condition. To treat such a collisionless plasma, the electrons and ions comprising the plasma are treated as individual particles. In such cases, it is a good approach to use the electromagnetic particle code in which the electric field and the magnetic field are solved progressively in time according to Maxwell's equations.To reconstruct on the computer, the environment around the spacecraft flying in space as closely as possible, the authors are developing the electromagnetic particle code in which the spacecraft is included as an internal boundary. This paper reports the numerical experimental results on the electromagnetic environment around the satellite which is formed when the spacecraft is exposed to a high‐speed plasma flow in a space plasma. A plasma flow is given from one end of the free boundary, and a spacecraft is placed in such a flow. By changing the parameters of the plasma, the physical quantities controlling the generation of the disturbance are found. In regard to the mechanism of the disturbance generation and the two‐dimensional configuration of the disturbance, several characteristics different from those predicted are obtained.