Fig. 4. C-N-S delivery via a giant planetary impact with proto-Earth and the results of inverse Monte Carlo simulations used to obtain the composition and the mass of the impactor.

(A) Illustration showing the merger scenario of a volatile-bearing planetary embryo with a C-saturated, S-rich core to volatile-depleted proto-Earth. (B) The alloy/silicate ratio and the bulk S content are mutually dependent on the S content in the alloy of the impactor (the controlling variable from our experiments and calculations). (C) The bulk C content of the impactor as a function of the bulk S content as well as the alloy/silicate ratio of the impactor that yields possible volatile delivery solutions. Various chondritic meteorites are also plotted for comparison. (D) The mass of the impactor is constrained in a narrow range similar to that of Mars.