Residuals of the transit fit as a function of the roll angle of the satellite for transit number 8. A clear dependence is seen which is well fitted with a non-parametric GP model overplotted in orange (see Sect. 2.3.1). The best fit length scale hyper-parameter in this case was degrees. The flux dependence with a roll angle is clearly seen in all our light curves, but the shape of the dependence varies.