Positions of large particles emitted by the nucleus on 2016 March 6, with velocities ranging from 0 to 3 m s⁻¹ observed on 2017 May 12 marked with light grey dots in the plane of sky. The coordinates mark offsets from the position of the nucleus for that time. For clarity, only a subset of the particles is plotted. The particles matching the position of the three head features are marked in blue. Those matching the arc are marked in red (the ends of the feature are marked in magenta and black); the blob at the western start of the linear feature (Fig. 2) is marked in orange.