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Boccaletti+ (2015) discovered features moving within the AU Mic debris disk at super-Keplerian tangential velocities in spatially resolved imagery of the AU Mic debris disk. To date comma these are the only moving structures seen in spatially resolved imagery of debris disks. The surface brightness comma number comma morphology comma and velocities of these moving features constrains their physical location and mass comma and thus are critical quantities needed to constrain the origin of this phenomenon. We propose 7 orbits of HST-STIS time per cycle comma for cycles 27 comma 28 comma 29 comma to determinedoublePoint a) What is the surface brightness of all features comma and how does the surface brightness and morphology of features change over timequestionMark b) What is the detailed vertical motion of features comma and does the amplitude of this motion depend on stellocentric separationquestionMark and c) What is the motion of the newly found features (NW-gamma and NW-delta) on the NW-side of the diskquestionMark These data will be used to test hypotheses that predict features are caused by the stellar wind expelling grains originating from a parent body that orbits at 8+--2 au (Sezestre+ 2017) or by interaction between the star.s wind and repeated dust avalanche events (Chiang and Fung 2017).