Notes. Measurements of Saturn’s thermodynamic temperature are accompanied by two uncertainties, the first spans the systematic scatter in the measurements within the frequency band and the second is the scatter due to background confusion. In estimating this thermodynamic temperature, we have subtracted contributions from Saturn’s rings; the quoted value therefore only refers to the thermodynamic temperature of the planet disc. For Jupiter, the systematic in-band scatter dominates any statistical noise, therefore the uncertainty from background confusion is omitted. Absolute thermodynamic temperatures of the planets can be obtained by adding the spectral radiance from an occulted CMB monopole (see Sect. 2.1.3).