Langmuir probe (LP) operations on CubeSats impact spacecraft (SC) charging levels due to the limited ion-current collection to the SC conductive surface relative to the electron current collection to the LP. This variable, net-negative SC potential will introduce errors in temperature and density measurements limiting the effectiveness of LPs. One method of counteracting the effects of a variable spacecraft potential is the twin-probe method (TPM), where the SC potential is directly measured during LP operations by using a separate high impedance probe. Experiments have demonstrated the feasibility of the twin-probe method as the SC to LP current collecting surface area ratio decreases; however, there remained unanswered questions due to chamber effects. To predict the SC’s charging behavior in a space plasma and understand how Langmuir probe measurements are impacted by a variable SC potential, a numerical model was developed called the Plasma Spacecraft Interaction Codes. Here, we present the general results of the model and compare them to chamber measurements that highlight good agreement between model and experiment results. Then, we will discuss the effectiveness of the TPM over a range of parameters such as area ratio and the input impedance of the high impedance probe.
Plasma Spacecraft Interaction Codes: Model for Langmuir Probe Operation on Small Spacecraft
Journal of Spacecraft and Rockets ; 62 , 3 ; 1044-1052
01.05.2025
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch