An Iron-Rich Sun and Its Source of Energy
  Mass-fractionation enriches light elements and the lighter isotopes of each element at the solar surface, making a photosphere that is 91 percent H and 9 percent He. The solar interior consists mostly of elements that comprise 99 percent of ordinary meteorites (Fe, O, Ni, Si, S, Mg and Ca) elements made in the deep interior of a supernova. Solar energy arises from a series of nuclear reactions triggered by neutron-emission from the collapsed supernova core on which the Sun formed. Solar mass-fractionation, solar neutrinos, and the annual solar-wind outpouring of 3 E43 H atoms from the solar surface are by-products of solar luminosity. 
O. Manuel and A. Katragada