Observed and modeled 8.25-µm brightness temperature (T_B). 8.25-µm T_B for Obs. 18 (leading side, first row) and Obs. 27 (trailing side, second row), plotted as a function of local time (first column) or latitude (second column). The data are color-coded according to latitude (i.e., to equal values of the latitude difference from the sub-observer point) in the T_B vs local time plots, and according to local time in the T_B vs latitude plots. In the third and fourth columns, the data are compared to one of the best models, that includes both a rescaling of the Bond albedo map and surface roughess (see text). In these panels, data are in black, models in red, and the data minus model difference in blue, with the 0 value indicated by the dashed line. Parameter values and rms of fit are indicated in each panel.