Core radius as a function of the redox state of the mantle (left) and the FeO content in the mantle (right) for the different compositions. The value for the MoI is indicated by different colors. The permissible ranges of ﹩\mathrm{log}{f}_{{{\rm{O}}}_{2}}﹩ relative to the IW buffer and ﹩{X}_{\mathrm{FeO}}^{\mathrm{Mantle}}﹩ for the Earth estimated from our model are shown as gray shaded regions. Even without further constraining the MoI, the core size of Venus could be constrained from the mantle composition alone.