The influence of the upstream conditions on the plasma convection in the distant tail lobes

Abstract:

In order to study the plasma convection in the distant magnetotail lobes near lunar orbit, we studied ions which originated from the tenuous exosphere and surface of the Moon. The data utilized are measured by the Acceleration, Reconnection, Turbulence, and Electrodynamics of Moon's Interaction with the Sun (ARTEMIS) spacecraft. Since the typically large positive spacecraft potential, the plasma convection is difficult to be directly measured in the tail lobes. In this work our result reveals that in the terrestrial magnetotail near the Moon, the lobe convection can be approximated by measuring the lunar ions velocity. Understanding how the lobe convection responds to the upstream conditions including the solar wind parameters and the magnetospheric activity index is important. Based on the analysis of multiple ARTEMIS observations and OMNI data in the statistical point of view, we found that the Interplanetary Magnetic Field and magnetospheric activity may play an important role in influencing plasma convection in the near-Moon lobes.