Geysers' Dust Dynamics Inside the Hill Sphere of Enceladus

Abstract In this work, we study the trajectories of the dust particles ejected in the geysers of the moon Enceladus, inside its Hill sphere, where its gravitational influence dominates. Our goal is to determine the properties of the particles that escape from the moon or of those that eventually impact on its surface. The analysis considers the gravity of Enceladus, the Lorentz force due to Saturn's magnetic field and the gas drag from the geysers. The local magnetic field around Enceladus is derived from an interpolation of Cassini data from six flybys. In general, we obtain that grain sizes and launching speeds define whether grains escape, though the launching angle may also play an important role in some cases.