Models with variable thermal inertia in the spot region. In these models, the spot phase integral is kept at the same value as in the no-spot region. The green, black, and blue curves are for Γ = 0.1 MKS and q = 0.778 outside of the spot, and Γ = 0.0, 0.1, and 0.2 MKS in the spot. The red curve represents the second best fit model at 100 μm with Γ = 0.0 MKS and q = 0.851 outside of the spot, and Γ_spot = 0.05 MKS in the spot.