Core composition (1)

• Outer core: liquid metallic alloy

  • mainly Fe + S and O likely
    + Si, Ni, H, Mg
    less probable, less significant
  • arguments based on
    • abundance in mantle relative to cosmic abundances (but losses due to volatility have to be considered too),
    • ability to form alloys as seen in laboratory experiments and meteorites,
    • ability to lower the core density.