Figure 5.

The CONSERT sounding of the ‘head’ of 67P. The panels display the signal delay (the measured signal travel time between orbiter and lander) versus time with the colour-coded linear amplitude of the sounding signal. The cross-cut profiles of the signal delay pattern are narrow indicating very little dispersive scattering by mass-cons or voids. The two panels show differences in the signal delay pattern: multi-path propagation is seen for the sounding of the evening side, but not on the morning side of the comet ‘head’ which may indicate variations, e.g. structures, in the electric permittivity of the material and/or reflections of sounding waves. The figure is adapted from Kofman et al. [19]. (Online version in colour.)