Top: ACS/WFC F555W image of PDS 144. Arrows (not to scale) show the magnitude and direction of proper motion for PDS 144 N, PDS 144 S, and TYC 6782-878-1 as well as that of background objects seen nearby in the field: (1) uncataloged field star (seen directly between PDS 144 N & S), (2) uncataloged field star, (3) 2MASS 15491411-2600598, and (4) 2MASS 15491748-2600499. Bottom: chart illustrating the proper motions of the stars seen in the ACS/WFC F555W image above. The gray ellipse encompasses the proper motion of stars in Upper Sco A. It was generated from the list of Upper Sco A stars in Köhler et al. (2000) that also had proper motion measurements available in the literature. Note: error bars are 3σ.