Proper motion of the peaks in the Sgr celestial frame as a function of . Top: coordinate of the kinematic structures detected, weighted by the number of stars in each peak. Bottom: same, but in . The footprint of the Sgr stream is clearly distinguishable in both the leading and trailing arms. In the latter, we note a sharp edge and a diffuse component above and below it (top and bottom panels, respectively). The lines represent the upper and lower limits of our kinematic selection.