MASSETTI, StefanoStefanoMASSETTIMANGANO, VALERIAVALERIAMANGANOMILILLO, AnnaAnnaMILILLOMURA, AlessandroAlessandroMURAOrsini, S.S.OrsiniPlainaki, C.C.Plainaki2021-02-022021-02-0220170094-8276http://hdl.handle.net/20.500.12386/30147We report 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 the Télescope Héliographique pour l'Etude du Magnétisme et des Instabilités Solaires (THEMIS) 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 also exhibits fluctuations in the time range of tens of minutes.STAMPAenArticle10.1002/2017GL0730902-s2.0-85017416514000400186500001https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2017GL0730902017GeoRL..44.2970MFIS/05 - ASTRONOMIA E ASTROFISICA