Simulation of Space Platform Charging in Very Low Earth Orbit Using Stochastic Particle Methods

TL;DR

This paper models space platform charging in Very Low Earth Orbit using stochastic particle methods, revealing how ionospheric plasma distributions influence satellite drag and lifetime.

Contribution

It introduces a hybrid Particle-in-Cell model incorporating Boltzmann electrons and Kappa distributions to improve simulation accuracy and efficiency.

Findings

Kappa distributions significantly affect platform charging.

Hybrid models reduce computational time while maintaining accuracy.

Ionospheric drag is a notable but partial component of total drag.

Abstract

The residual atmospheric drag on satellites in Very Low Earth Orbit (VLEO) has been recognized as a limiting factor for satellite lifetimes. This work focuses on one component of the drag, i.e., the ionospheric drag from charged particles, which was observed to influence the overall aerodynamics of satellites. Space platform charging processes are modeled using a stochastic particle method, Particle-in-Cell, with with the possibility to treat the electrons as a Boltzmann fluid, thus reducing the computational time while preserving the accuracy of the physics of charging. Part of the study involves examining non-equilibrium distribution functions, specifically the Kappa distribution, commonly used to describe space plasmas. It has been shown that such distributions can noticeably affect overall space platform charging, thereby enhancing ionospheric drag on satellites using the proposed hybrid models. Nevertheless, it is acknowledged that ionospheric drag might constitute only a fraction of the total drag caused by neutral atmospheric gas.