Gravitational moment distribution for successful Uranus (a) and Neptune (b) profiles. Both panels include a 2D histogram where bins more frequently occupied by solutions are shown with a relatively darker colour. Additionally, 1D histograms display the weighted number of solutions along each axis. The weights were assigned to solutions based on a multivariate Gaussian likelihood, with means, standard deviations, and covariance taken from Table 1. In the left panel a, an orange distribution is shown in addition to the blue distribution. Both blue distributions in (a) and (b) assume cov(J₂, J₄)=0, whereas the orange distribution for Uranus takes cov(J₂, J₄)=0.9861 σ_J2 σ_J4.