Wind Momentum Budget of the Central Star of the Ghost of Jupiter NGC 3242

This paper computes a self-contained budget for NGC 3242 from published observational values, with every derived number produced by the deposited computation script. The Ghost of Jupiter Nebula has a bright inner shell, a fainter outer shell and a central star with a fast radiation-driven wind whose terminal velocity exceeds two thousand kilometres per second. The mechanical output of that wind can be compared with the radiative output through the wind momentum ratio, the standard diagnostic of whether a wind is driven by single scattering of photons or requires multiple scattering. The same wind, acting over the nebular lifetime, supplies the energy that shapes the inner shell, so its integrated budget connects the present stellar spectrum to the nebular The headline results are: mass_loss_rate_Msun_yr = 2e-08; terminal_velocity_km_s = 2.4e+03; wind_momentum_ratio = 0.395; wind_power_W = 3.63e+27; wind_power_Lsun = 9.48; nebular_age_yr = 7822; integrated_wind_energy_J = 8.96e+38. The momentum ratio is below unity, so the wind does not require multiple scattering and is consistent with ordinary line driving. The integrated wind energy over the nebular age is more than sufficient to account for the kinetic energy of the inner shell, leaving room for the substantial radiative losses such shells are known to suffer. The wind budget therefore supports, rather than strains, the interacting-winds picture for this double-shell nebula. The calculation is presented with its inputs, relations and sensitivities stated openly, so that any revised distance, density or stellar parameter can be substituted and the verdict recomputed directly.