Sandstorm (Abridged)

The Sun as now studied is far removed from its early models that described a homogeneous spherical body: chemical fractionation as well as considerable fine-structure in and above the solar surface and internal mixing must now be taken into account. Accordingly, attention in composition studies has shifted from absolute solar abundances toward differences in the chemical (and isotopic) composition of the different parts of the Sun: in its interior, in the structures that make up its atmosphere, …