Evolution in the Hertzsprung‐Russell diagram for a star of mass M_* = 0.10 M_☉. Each small filled circle delineating the evolutionary track represents a separate converged model. The star begins its evolution on a pre–main‐sequence Hayashi track and ends up as a helium white dwarf, cooling into obscurity. The inset diagram shows the chemical composition of the star over the course of its evolution; the mass fractions in H, ³He, and ⁴He are plotted as functions of time.