Observations of current sheets associated with solar wind reconnection exhausts passing through the near lunar wake

Two reconnection exhausts were detected by one of the dual ARTEMIS orbiters in the solar wind near the Moon. Almost meanwhile, the other ARTEMIS orbiter encountered the two corresponding current sheets at the relatively marginal and central locations in the near lunar wake. Due to the Moon's direct absorption, the current density of the current sheet disappears within the wake. As a result, the wake magnetic field around the current sheets is changed. It is found that the variations of the magnetic field in the wake are primarily governed by two factors: diamagnetic current system at the wake boundary and the dropout of M direction currents (jM) within the wake. Instead of being almost unaltered as commonly assumed in the study of lunar wake, the magnetic field of the current sheets becomes potential with almost zero current density. With respect to the solar wind magnetic field, this potential magnetic field is weaker in the center and has an X line-like configuration with significant normal components in the marginal portions of the wake. Our result may be applicable to nonconducting or weakly conducting contexts widely existing in the universe.