Time series of (a) GOES measured X-ray irradiance (where each peak corresponds to a flare), (b) Rosetta’s distance to the comet nucleus, (c) the heliocentric distance of Rosetta, and (d) the heliospheric longitudinal separation between Rosetta andEarth as well as between Rosetta and Mars. The colored vertical lines at the top indicate the cataloged C, M, and X class flares that were observed at Earth and occurred during the Rosetta mission, which were also directed such that Rosetta could observe them. Those that were not detectable (ND) because of the geometry (too far out on the limb of the Sun) are indicated by the black lines.