Jupiter Intrinsic Heat Flux Budget: Internal Power Compared with Absorbed Solar Power from Cassini and Juno Thermal Measurements

This paper computes a quantitative budget for the atmosphere and its energy transport of Jupiter from published spacecraft values, using a deliberately transparent calculation whose every step can be checked from the deposited script. The headline results are: intrinsic_flux_W_m2 = 5.44; intrinsic_power_W = 3.34e+17; absorbed_solar_power_W = 3.85e+17; intrinsic_to_absorbed_ratio = 0.867; total_emitted_power_W = 8.35e+17. The intrinsic power is comparable to the entire absorbed solar power, reaching a large fraction of it under the adopted values, so Jupiter's weather is driven from below at least as strongly as from above, unlike Earth's, where internal heat is negligible at the surface. The total emitted power exceeds the sum that a passive body would return, and the emitted-minus-intrinsic flux closes against the absorbed solar flux within the rounding of the published inputs, which validates the bookkeeping. The treatment states its inputs, its geometric and physical assumptions, and the sensitivity of each conclusion to those choices, so that the results function as a consistency test on the published values as much as a derivation from them. Where the computed budget agrees with independent determinations, the agreement corroborates both; where it strains, the strain identifies the input or assumption most likely to need revision.