Vesta, the next-most-massive body in the asteroid belt after Ceres, was once in hydrostatic equilibrium and is roughly spheroidal, deviating mainly due to massive impacts that formed the Rheasilvia and Veneneia craters after it solidified. Its dimensions are not consistent with it currently being in hydrostatic equilibrium. Triton is more massive than Eris or Pluto, has an equilibrium shape, and is thought to be a captured dwarf planet (likely a member of a binary system), but no longer directly orbits the sun. Phoebe is a captured centaur that, like Vesta, is no longer in hydrostatic equilibrium, but is thought to have been so early in its history due to radiogenic heating.