We consider the generalized Stormer Problem that includes the
electromagnetic and gravitational forces on a charged dust grain near a planet.
For dust grains a typical charge to mass ratio is such that neither force can be
neglected. Including the gravitational force gives rise to stable circular orbits
that encircle that plane entirely above/below the equatorial plane. The effects
of the different forces are discussed in detail. A modified 3rd Kepler’s law is
found and analyzed for dust grains.
This is a pre-print. The definitive version: DULLIN, H.R., HORAYNI, M. and HOWARD, J.E., 2002. Generalizations of the Stormer problem for dust grain orbits. Physica D - Nonlinear Phenomena, 171(3), pp.178-195, is available at: http://www.sciencedirect.com/science/journal/01672789.