Along-scan residuals against G magnitudes. The grey points represent all observations. The coloured points are the observations that were accepted by the orbit adjustment procedure after outlier rejection chosen at |O − C| > 5 σ. For G_mag < 11.5, the distribution is not Gaussian. This is clearer in Fig. 6. For G_mag ≥ 11.5, the distribution is Gaussian. The orange lines in the plot are ±1 σ, the blue lines are ±2 σ, and the yellow lines are ±3 σ. The number density is given by the scale on the right.