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tokens: in November 2014 (red; Snodgrass et al. 2016 ). 3.2 Dust coma morphology and activity For each cube in our dataset, we extracted maps over the bandpasses of the V , R , and I Johnson-Cousins filters. All maps in the same bandpass were re-centred and then co-added. The resulting co-added maps are displayed in the top part of Fig. 2 . The dust coma morphology is the same for all three bandpasses. It is asymmetrical, likely due to the presence of dust jets. To investigate the presence of jets further, we divided the dust maps by an azimuthal median profile ( Samarasinha et al. 2013 ). Enhanced maps are displayed on the bottom part of Fig. 2 . Here, we can clearly see two jets, which are most likely the cause of the apparent asymmetry of the dust coma. The first jet is located close to the anti-sunward direction, towards the south-west. The second jet is located about 90° away, towards the south-east. Finally, we see a faint feature towards the sunward direction. Those jets are consistent with what was observed on previous passages and what is reported by Knight et al. (2017) and Snodgrass et al. (2017a ) from observations at the same epoch. They are also consistent with the modelling of the pole orientation and active region location done by Vincent et al. (2013) prior to the Rosetta mission. In addition to the two jets mentioned above, we see an enhancement towards the North-West. This corresponds to the dust trail that was reported to be at least two degrees long at that epoch ( Snodgrass et al. 2017a ; Boehnhardt et al. 2016 ; Knight et al. 2017 ). We do not see changes of the coma morphology over the five nights of our observations, nor over a single night. To constrain the comet activity at that time, we compute the Af ρ value, which is a proxy for dust production, as defined by A’Hearn et al. (1984) . We compute the Af ρ for the V , R , and I bands over a 2500 km physical aperture. We use a 2500 km aperture instead of the more commonly used 10 000 km aperture because the comet signal drops significantly at 10 000 km. We obtain values of 65 ± 4 cm, 75 ± 4 cm, and 82 ± 4 cm in the V , R , and I bands, respectively. Those values have not been corrected for the phase angle effect and are consistent with those reported by Boehnhardt et al. (2016) at the same epoch, and they are comparable (even though slightly lower) to those reported by Knight et al. (2017) once the phase angle effect is taken into account. Using the Af ρ values in the different bands, we can also compute the dust reflectivity gradient defined as ( Jewitt Meech 1986 ): where Af ρ x and the corresponding wavelength λ x are expressed in cm and nm, respectively. For the I – V combination, this gives a reflectivity gradient of 7 ± 1%∕100 nm, while it is of 11 ± 2%∕100 nm for the R – V and 7 ± 1%∕100 nm for the I – R combination. This confirms the trend outlined in Sect. 3.1 of higher reflectivity gradient at lower wavelengths. To check for trends with the aperture size, we