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Juno and HST form a powerful and unique combination to unravel the processes coupling the Jovian magnetosphere to its atmosphere through its auroras. As an example comma context images of the UV auroras offered by HST help making sense out of the Juno in situ measurements and disentangle spatial from temporal effects. As Juno.s orbit evolves comma new challenges and opportunities emerge during cycle 28. In particular comma Juno will fly at lower and lower altitudes over the north pole comma potentially accessing the deepest part of the region where the charged particle causing the aurora get accelerated. Unfortunately comma Juno.s remote sensing instruments will be too close to Jupiter and Juno will fly to fast in the North to offer global images of the auroras associated with the in situ wave comma field and particle measurements. Only HST is able to provide the spatially resolved UV images critical to properly interpret the data. Furthermore comma Juno will cross the magnetic equator closer and closer to Jupiter comma exploring new areas where some key physics for the dynamics of the plasma in Jupiter.s magnetosphere takes place. Simultaneous global images with the STIS instrument will allow the identification and classification of the structures crossed by Juno as well as estimates of their spatial range and temporal variability. In return comma Juno will unravel the plasma processes giving rise to the auroral feature imaged by HST. Finally comma we will take advantage of a rare opportunity for truly simultaneous imaging of the two polar auroras of Jupiter when Juno is in the southern hemisphere to shed light on the mystery of the conjugate auroral flares in the polar-most region of the Jovian auroras.