Left panel: r−z-diagram of J1644 using the Tillich et al. (2011) proper motion (top) and the weighted mean of the catalogue proper motions (bottom), respectively. Right panel: disk passages binned and colour-coded of J1644 with 1 and 3σ contours using the Tillich et al. (2011) proper motion (top) and the weighted mean of the catalogue proper motions (bottom), respectively. The black dot marks the GC, the star the current position of J1644, and the solar symbol the position of the Sun. The circle indicates the Galactic disk. All calculations were performed with model I of Irrgang et al. (2013).