A geometric approach to the equilibrium shapes of self-gravitating   fluids
  The classification of the possible equilibrium shapes that a self-gravitating fluid can take in a Riemannian manifold is a classical problem in mathematical physics. In this paper it is proved that the equilibrium shapes are isoparametric submanifolds. Some geometric properties of the equilibrium shapes are also obtained, specifically the relationship with the isoperimetric problem and the group of isometries of the manifold. This work follows the new geometric approach to the problem developed by the author (see math-ph/0305038) 
Daniel Peralta-Salas