Orbit for HIP 2505 = WDS 00318+5431. The left plot shows all observations, with those that are more than three 3 × se from the final orbit marked with x’s and not used in the fit. These observations are removed from the same orbit on the right plot. In both plots, the area of the filled circles corresponds to the weights given to the observations. Points after 2011 are our AO observations, except for the two nearly co-located circled points, which are two 2019 SI observations that have been adjusted by 180^∘ from across the plus at the center, coincidentally along the line of nodes. The line of apsides and the line of nodes are drawn, as well as the velocity vectors at their ends, which are the periastron q and the ascending node Ω. Years are indicated by blue open diamonds.