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tokens: hemisphere (57 deg south). This configuration is ideal for jet monitoring because it provides a view of all local times in a single frame, and the nucleus rotating in front of the camera gives the stereographic views without the need for different spacecraft pointing. From a distance of 29 km, we achieved 3 m/px resolution with the WAC. We found that many more sources were active at that time (at least 10 jets per image), and we could trace them down to the surface (Fig. A.5 ). We consistently found sources on high slopes, such as cliffs and walls of alcoves and pits. There is very little evidence of any activity arising from smooth, flat areas, apart from the larger scale activity in Hapi. The Hapi activity was associated to terrains displaying bluer spectral slopes; when comparing our sources with published color maps by OSIRIS ( Fornasier et al. 2015 ; Oklay et al. 2015 ) or VIRTIS Capaccioni et al. (2015) , it seems to also be true for the smaller sources. It is particularly interesting to see that new jets arise from areas identified as bluer in early images August 2014 but not yet active at that time. Figure 2 shows an example of such a source. Figure A.5 summarizes all inverted sources. Fig. 2 Left panel : map of sources active in December 2015, projected on the 3D shape model of 67P. Right : close-up view of an RGB color composite showing one of the sources with a typical bluer hue, corresponding to the location of the white box in the left panel . The color image reflects the variegation of the terrain in August 2014, when this area was not yet active. Distance from the comet center: 43 km; resolution: 0.75 m/px. The large block in the center is about 100 m wide. Reference image: NAC_2014-09-05T06.35.55.557Z_ID30_1397549300_F22. Active spots are typically observed closer to the equator than in September 2014, actually within 30 of the subsolar latitude. Inverted sources are listed in Fig. A.5 . We also observed that sources switch on and off within 20 min of crossing the terminator, this duration being an upper limit constrained by the cadence of our observations. This is particularly striking for sources in Seth and Hapi, which experience very different diurnal illumination. They are typically illuminated only for three consecutive hours before entering three hours of night because of the strong self-shadowing introduced by the large concavity of the nucleus. As a result, they experience two day/night cycles per nucleus rotation. 3.3. Sources in April 2015, 2 AU, subsolar latitude +9.8<inline-formula specific-use="simple-math">°</inline-formula> The same trend in spatial distribution and behavior of sources is confirmed with later sequences. Our next inversion of a sequence acquired in March 2015 again shows that sources lie close to cliffs, and their average latitude has migrated south, following the Sun. We start to observe new regions becoming active close to the equator in the Ma’at and Imhotep regions (Fig. A.5 ). As we get