Sulfur in mercury's core?

New models of Mercury's internal structure are calculated for different amo unts of sulfur in the core. The density of an FeS core differs by only abou t 0.5% from the mean density of Mercury. A determination of Mercury's momen t of inertia will effectively discriminate among the models and place relat ively tight constraints on the radius and sulfur content of the core despit e relatively large uncertainties in the density and temperature of the sili cate mantle. (C) 2001 Academic Press.