Gaia mean reflectance spectrum of the asteroid (1) Ceres, obtained at an average phase angle of 17.5°, plotted with solid circles. Literature ground-based spectra from Bus & Binzel (2002b) and Lazzaro et al. (2004) are shown with a grey line (phase angle of ∼18.6°) and a black line (phase angle of 16°), respectively. Data obtained in space by the NASA Dawn mission (Li et al. 2016) during RC1 are displayed with black open squares (phase angle between 17.2 and 17.6°), and during the RC2 with black open triangles (phase angle 42.7 to 45.3°).