Dawn-Dusk asymmetry in Jupiter’s main auroral emissions

Previous studies of Hubble Space Telescope’s (HST) observations of the UV main auroral emissions at Jupiter indicate that the dusk side of the aurora is brighter than the dawn side, contrary to some theoretical expectations. However, images from the HST suffer from an incomplete view of the pole and from a selection bias related to the inclination of the magnetic dipole. Now that Juno is orbiting Jupiter, more data and better views of the auroral regions are being collected. Using UVS, the UV spectrograph on board Juno, we can create comprehensive maps of the auroral regions for both the northern and southern hemisphere, without any orientation bias. Based on Juno’s 39 first perijoves and using the model of Jupiter’s magnetosphere from Vogt et al. (2011), we could isolate the auroral features associated with the dawn and dusk sectors. Then, we derive the power emitted by the dawn and dusk parts of the aurorae and compare our results to the previous HST observations.