Left: Offsets of SGR 0501+4516 in 2D-projected equatorial coordinates in each of the three HST epochs (note that epoch 2020.6 has observations in two filters) with respect to the mean position across all four sets of observations. Dark and light shaded ellipses correspond to the 1 and 3 σ uncertainties, respectively. Right: Linear fits to positional offsets of SGR 0501+4516 in α_⋆ and δ, including corrections for solar and Galactic motion, as a function of time. The uncertainties on the points show the overall positional uncertainties on SGR 0501+4516 at each epoch, including residuals from the astrometric tie to the Gaia Early Data Release 3 reference frame. The two 2020 points are from the two filters, and the rightmost marker in the right-hand panels has been arbitrarily shifted by 0.15 years for visual clarity. The best-fit proper motions in each coordinate are indicated, and a shaded region indicates the 1σ uncertainty on the fit.