Extended Data Fig. 8: Interior structure modeling constraints.
From: A warm Neptune’s methane reveals core mass and vigorous atmospheric mixing
A corner plot of the posterior mass (MJ), radius (RJ), envelope metallicity (unitless), core mass (M⊕), and intrinsic temperature (K). The model inputs (from observations) are shown in the upper-right, and the priors were weakly-informative. The overall bulk metallicity is set by M, R, and Tint, and can be seen as an arc in Ze-Mc space. Our atmospheric constraint restricts us to a section of this arc; without it, the two parameters would be fully degenerate, running from Mc = 0 on one side to Ze = 0 on the other, though the effect on Zp would be much more limited. The intrinsic temperature is significantly higher than unheated evolution models would produce, and is thus evidence of tidal heating (see text).
