Jupiter emits at about 130 K rather than the solar-only estimate around 111 K. Intrinsic <heat> contributes additional outgoing flux, so $\sigma T_{\mathrm{emit}}^4=F_{\mathrm{absorbed}}+F_{\mathrm{internal}}$. The difference of <Fourth power>[fourth powers] is the relevant <energy> excess, not their direct <temperature> difference. Cooling and contraction of the interior provide the main physical motivation for including this extra term.

Solution

Past exam of the short options paper shared by Prelims and Parts A and B of the physics course of the University of Oxford / 2016 / S29 / 1 / 4 / b / Solution

 Solution (source code)