Plasma waves and newly formed ions near Jupiter

Inside Jupiter's and Saturn's magnetospheres, new ions form when neutral particles are ionized by the Sun's energy, electron impacts, and charge exchange.

These new ions interact with the plasma, an electrically conductive ionized gas in the magnetosphere. These interactions generate waves in the plasma, phenomena that have been observed by spacecraft. To understand the degree to which perturbations in plasma affect the space environment, Cowee et al. sought to characterize plasma waves generated by the formation of new ions, specifically sulfur dioxide ions, released from the atmosphere of Jupiter's moon, Io. Previous research had suggested that newly formed ions lose 50 percent of their energy to plasma wave generation, but the authors used simulations to show that at most, about 25 percent of the energy of the newly formed ions is lost to wave growth for conditions at Io. Thus, more ions than previously thought are required to generate the plasma wave energies observed.-American Geophysical Union