Isolated transient UV auroral structures at Jupiter: possible signatures of magnetospheric injections

We investigate transient ultraviolet auroral features located equatorward of the main emission (130 features) based on Hubble Space Telescope (HST) observations of the northern and southern Jovian hemispheres (2000-2007). Several properties of the auroral emissions are analyzed, such as their position in auroral region, power and brightness. Additionally, we magnetically map the auroral structures to the equatorial plane using VIPAL model and we compare their observed properties with those of magnetospheric injections observed by Galileo. We suggest that these transient auroral structures could be related to magnetospheric injections. The mapped radial position and system III longitude of the observed auroral features are in good agreement with those of the injections observed in the equatorial plane by Galileo. Based on power and brightness of the auroral features, we discuss the mechanisms involved in the ionosphere-magnetosphere coupling injections. This comparative study demonstrates that the structures under study are related to magnetospheric injections and sheds light to the mechanism involved in the magnetosphere-ionosphere dynamics.