Figure 3.

The incoming solar radiation as a function of latitude for Enceladus, the moon of Saturn. Both the numerically integrated and the analytic approximation are shown, and the two are almost indistinguishable except for the region around latitudes −π/2 + ε and π/2 − ε (63^∘S and 63^∘N), at the transition to the polar regions. The parameter values we used to calculate the incoming solar radiation to Enceladus are: S₀ = 15.14 W m⁻², e = 0.055, ε = 27^∘, and α_p = 0.8. For simplicity, to estimate the incoming solar radiation during the solstice, we assume that e = 0.