A research team at Lab of Solar System Exploration, National Space Science Center (NSSC) has recently presented a three-dimensional magnetohydrodynamic (MHD) simulation of the lunar wake to further our understanding of the Moon-solar wind interaction.
By establishing a 3D MHD model with high spatial resolution, PHD candidate XIE Lianghai, with his supervisor Dr. LI Lei and colleague Zhang Yiteng studied three cases in which the interplanetary magnetic field lies at 90。, 180。and 135。to the solar wind flow. Some basic features of the interaction were revealed, including the plasma density decrease in the wake and the central wake magnetic field increase.
The model also shows that the plasma temperature is enhanced in the void and an acceleration region may appear in the near wake. More than that, as the plasma moves into the wake, some rarefaction waves propagate away from the limb via the fast magnetosonic mode, which is anisotropic and propagates with different velocities.
Compared with previous global models, one of the advantages lies in its self-consistent way of handling all variables without any simplification. And results show consistency with WIND spacecraft observations.
Applying a parallel and adaptive mesh refinement (AMR) technology, the model gets a fine structure of the lunar wake. It will contribute to the space weather forecasting or in other words, it enables us to predict lunar space environment, therefore guarantees a successful space exploration program such as the Chang'E Project.
Supported by National Natural Science Foundation of China, the simulation results were obtained under the Space Weather Modeling Framework, developed by the Center for Space Environment Modeling, University of Michigan. Results were published on Science China Earth Science, doi:10.1007/s11430-012-4383-6.(Full Text).
Lab of Solar System Exploration, National Space Science Center,