In Situ Investigations of Dust Above the Lunar Terminator at the Chang'E-3 Landing Site in the Mare Imbrium

It was suspected that the horizon glow observed over the lunar terminator was caused by electrostatically levitated dust particles, but do high concentrations of dust particles really exist over the lunar terminator? This is an important question that cannot be answered even today. In fact, no in situ investigations about the lunar dust have been conducted on lunar surface since Apollo. Here we first report in situ investigations of lunar dust at Chang'E-3 (CE-3) landing site using solar cell probe (SCP). The results show that, different from Apollo's observation, the short-circuit current of SCP did not decrease sharply during the first several lunations except the first lunation, indicating the recently developed minimalist qualitative model of sunrise-driven dust transport might not be applicable at the geologically young CE-3 landing site. In addition, within detector's detection limit, no abrupt changes in dust concentration were observed above the sharp sunlight/shadow boundaries on lunar surface.