Plainaki, ChristinaChristinaPlainakiMassetti, S.S.MassettiMangano, V.V.ManganoMilillo, A.A.Milillo2020-09-172020-09-172017-09-01https://hdl.handle.net/20.500.13025/5254We illustrate the analysis of short-term ground-based observations of the exospheric Na emission (D1 and D2 lines) from Mercury, which was characterized by two high-latitude peaks confined near the magnetospheric cusp footprints. During a series of scheduled observations from THEMIS solar telescope, achieved by scanning the whole planet, we implemented a series of extra measurements by recording the Na emission from a narrow north-south strip only, centered above the two emission peaks. Our aim was to inspect the existence of short-term variations, which were never analyzed before from ground-based observations, and their possible correlation with interplanetary magnetic field variations. Though Mercury possesses a miniature magnetosphere, characterized by fast reconnection events that develop on a timescale of few minutes, ground-based observations show that the exospheric Na emission pattern can be globally stable for a prolonged period (some days) and can exhibits fluctuations in the time range of tens of minutes.conference paperhttp://meetingorganizer.copernicus.org/EPSC2017/EPSC2017-753.pdf5aba3e696c5e1b5a034b8b27