Interplanetary and interstellar dust particles acquire a positive charge in the solar wind and can be strongly influenced by the Lorentz force as they pass through planetary magnetospheres. There, the charge on the particles changes rapidly when they pass through different plasma environments. This can lead to exchange of energy and angular momentum with the magnetosphere. Here we describe the discovery of captured grains in Jupiter’s magnetosphere by the Galileo dust detector and numerical simulations of the captured dust ring.