Predicted apparent R-band magnitude of the comet, as measured within an aperture with ρ = 10   000 km, for 2014–2016. This covers the active phase of the Rosetta mission, including any extended mission beyond the end of 2015. Mission milestones in 2014 are marked: (a) Switch on of the spacecraft (January 20th, 2014); (b) Expected beginning of detectable activity, at 4.3 AU (March 2014); (c) The nucleus begins to be resolved by the OSIRIS Narrow Angle Camera on Rosetta (July 2014); (d) Orbit insertion (August 2014, at 3.5 AU); (e) Lander released (November 2014, at 3 AU). The observability of the comet from Earth is shown by hatched, cross-hatched and solid grey areas marking when the solar elongation is less than 50°, 30° and 15°, respectively. Perihelion (in August 2015) is marked by a vertical dashed line. At that time the comet will be 43° from the Sun, as seen from Earth. The lower 3 panels show various geometric parameters that describe the observability of the comet. Upper panel: solar elongation (solid line) and phase angle (dashed line); middle panel: declination; lower panel: heliocentric (solid line) and geocentric (dashed line) distances.