Estimation of Electrostatic Force on Solar Sail IKAROS in Solar Wind Plasma

We have numerically analyzed the electrostatic force on the solar sail IKAROS in solar wind plasmas at 1.0 AU. We estimated the electrostatic force quantitatively to understand if the force could affect the thrust of the solar sail generated by the solar radiation pressure. The estimation was made by Maxwell stress tensor method from the electric field on the spacecraft obtained by the charging analysis of the spacecraft. A 3-D electrostatic fullParticle-In-Cell code was used in order to study precise charged particle distributions and the space charge effects on the electrostatic potential around the solar sail. MUSCAT, a spacecraft charging analysis tool, was used to determine the differential voltage of the spacecraft. According to the numerical analysis, highest absolute value of the electric field was recognized on the edge of the back insulator surface of the membrane constituting the spacecraft. The maximum magnitude of the electrostatic tension on the surface was 1.0x10 -8 Pa, which corresponds to 1% of the magnitude of the solar radiation pressure under the solar wind environment considered.