  We consider the minimal energy problem on the unit sphere $\mathbb S^2$ in
the Euclidean space $\mathbb R^3$ immersed in an external field $Q$, where the
charges are assumed to interact via Newtonian potential $1/r$, $r$ being the
Euclidean distance. The problem is solved by finding the support of the
extremal measure, and obtaining an explicit expression for the equilibrium
density. We then apply our results to the external field generated by a point
charge, and a quadratic external field.
