Observational research on Mercury's magnetosphere

Mercury's miniature magnetosphere has no radiation belts, ionosphere, plasmasphere and atmosphere, only a weak exosphere. The induction effect of the planet's very large iron core is obvious. These result in a significant different space environment from that of the Earth. Observations of Mercury's magnetosphere by the MESSENGER spacecraft have enriched the knowledge and understanding of Mercury's space environment. Here, recent advances in Mercury's magnetosphere observational research are briefly summarized, from the aspects of magnetospheric scale and variability, magnetic reconnection and the formation of magnetic flux ropes, typical magnetospheric dynamic activity process, spatial and temporal variations of magnetospheric planetary heavy ions, magnetospheric response characteristics to the extreme solar events. Some related topics for the future exploration of BepiColombo mission are prospected.