Extended Data Fig. 3: Matching core seismic properties in the quaternary system inside the core.

Range of core compositions in the liquid Fe-Ni-S-X (X = C, O, H) quaternary system (blue regions) that match InSight observations (yellow regions) of core density (left column, panels a, d, g), core P-wave velocity (middle column, panels b, e, h), and both properties simultaneously (right column, panels c, f, i) inside the core. For purposes of illustration, only non-spin polarised ab initio molecular dynamics (AIMD) simulations are shown. Similar results are obtained using the spin-polarised AIMD simulations as indicated in Fig. 1 in the main text.