This paper presents a modeling and simulation study of the photoelectron sheath near uneven lunar surface. A fully kinetic 3-D finite-difference (FD) particle-in-cell (PIC) code is utilized to simulate the plasma interaction with local uneven surface terrain on the lunar surface in 2-D photoelectron sheaths. The code is first validated using a 1-D plasma charging and sheath problem by comparing with a semi-analytic solution. Good agreement is obtained. The 2-D FD-PIC simulations present the distributions of electric potential and charged species densities near the uneven lunar surface. It shows that the surface potential is highly influenced by the exposure to sunlight and local Sun elevation angle. Under average solar wind conditions, exposure to sunlight could lead to a positive surface potential with a magnitude of tens of volts, whereas the lack of sunlight results in a negative surface potential of several volts.

Meeting Name

AIAA Scitech 2021 Forum (2021 Jan. 11-15, 19-21, Virtual)


Mathematics and Statistics

Second Department

Mechanical and Aerospace Engineering

Research Center/Lab(s)

Center for High Performance Computing Research

International Standard Book Number (ISBN)


Document Type

Article - Conference proceedings

Document Version

Final Version

File Type





© 2021 The Authors, All rights reserved.

Publication Date

21 Jan 2021