Chords in the sky plane relative to Chariklo’s main body (in blue), C1R (in green), and their uncertainties (in red). Ellipses were fitted to C1R points. The black line stands for the best-fit ellipse, and all the ellipses in the 1σ region are in grey. Left panel: event on 2017 June 22. Right panel: event on 2017 July 23. For the sake of clarity, some redundant chords on 2017 July 23 were not plotted.