V. Hue(1), G. R. Gladstone(2,3), C. K. Louis(4), T. K. Greathouse(2), B. Bonfond(5), J. R. Szalay(6), A. Moirano(7,8), R. S. Giles(2), J. A. Kammer(2), M. Imai(9), A. Mura(10), M. H. Versteeg(2), G. B. Clark(11), J.-C. Gerard(5), D. C. Grodent(5), J. Rabia(12), A. H. Sulaiman(13), S. J. Bolton(2), J. E. P. Connerney(14) 

(1) Aix-Marseille Université, CNRS, CNES, Institut Origines, LAM, Marseille, France, (2) Southwest Research Institute, San Antonio, TX, (3) University of Texas at San Antonio, San Antonio, TX, (4) School of Cosmic Physics, DIAS Dunsink Observatory, Dublin Institute for Advanced Studies, Dublin, Ireland, (5) STAR Institute, LPAP, Université de Liège, Liège, Belgium, Liege, Belgium, (6) Princeton University, Princeton, NJ, (7) Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy, Rome, Italy, (8) Sapienza University of Rome, Rome, Italy, (9) Department of Electrical Engineering and Information Science, National Institute of Technology (KOSEN), Niihama College, Niihama, Japan, (10) Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy, (11) Johns Hopkins University Applied Physics Laboratory, Laurel, MD, (12) IRAP, Toulouse, France, (13) Minnesota Institute for Astrophysics, School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, (14) NASA Goddard Spaceflight Center, Greenbelt, MD, USA, (15) Space Research Corporation, Annapolis, MD, USA

Jupiter's satellite auroral footprints are a consequence of the interaction between the co-rotating iogenic plasma and the Galilean moons. Since the disturbance caused by the presence of the moons in the plasma flow propagates along the field lines in the form of Alfvén waves, the physical positions of the moons are magnetically connected to their respective footprint. The accurate determination of the footprint positions therefore provides an important physical reference point in Jupiter's auroral regions with respect to where they map in the magnetosphere. It also depends on the physical conditions near each of the moons (plasma conditions, variation in magnetic field amplitude, and magnetodisc topology). Juno's elliptical polar orbit around Jupiter allows Juno-UVS to produce a comprehensive satellite footprint dataset. We present an extensive analysis of the Io, Europa and Ganymede satellite footprints, and estimate observationally for the first time the corresponding Alfvén travel time at all system III longitudes, constraining the Alfvénic interaction at the 3 innermost Galilean moons.