Radial distances of the east and west emission peaks as a function of frequency in time-integrated images (left) and as a function of time in frequency-integrated images (right). The range of variation in the peak position with frequency is [1.43–1.67] R_J for the east peak and [1.30–1.78] R_J for the west peak. With time, it is [1.13–1.70] R_J for the east peak and [1.22–1.54] R_J for the west peak. Shaded surfaces represent an uncertainty of ± 1R_J.