Comparison between Virtis data (left) and the best fit with the roughness model (right) with Γ = 210   J   m^-2   K^-2   s^−1/2 and ξ = 0.20. We used 41 290 facets here for a better rendening with high spatial resolution. Warm surface is in yellow, while cold regions appear in dark red. Facets that are included in the selected 104 pixels are color-coded in temperature. North is up. The morning side appears in the middle while noon local time is on the right.