In this work we present the detection of CH4 and H3+ emissions in the atmosphere of Jupiter as two well separated layers, located, respectively, at a tangent altitudes of about 200 km and 500-600 km above the 1-bar level. We studied the vertical distribution of the two species retrieving their Volume Mixing Ratio (VMR) and temperature simultaneously or allowing only one quantity to vary. From this analysis, it is not possible to firmly conclude if the observed H3+ and CH4 features are due to an increase of their VMR or rather to variations of the temperature of the two molecules. However, our retrieval indicates that CH4 is in non-Local Thermal Equilibrium (non-LTE) condition, considering that the retrieved temperature values at about 300 km, where the maximum CH4 concentration lies, is always about 100 K higher than the Galileo measurements. We suggest that vertically propagating waves is the most likely explanation for the observed VMR and temperature variations in the JIRAM (Jovian InfraRed Auroral Mapper) data. Other possible phenomena could explain the observed evidences, for example a dynamical activity driving chemical species from lower layers towards the upper atmosphere, like the advection-diffusion processes responsible for the enhancement observed by Juno/MWR (MicroWave Radiometer), or soft electrons precipitation, although a better modeling is required to confirm these hypothesis. The characterization of CH4 and H3+ species, simultaneously observed by JIRAM, offers the opportunity for better constraining the atmospheric models of Jupiter and understanding the planetary formation.

Auroral brightness and color ratio imagery, captured using the Juno mission’s Ultraviolet Spectrograph, display intense emissions poleward of Jupiter’s northern main emission, and these are split into two distinctly different spectral or “color ratio” regimes. The most poleward region, designated the “swirl region” by Grodent et al. (2003), exhibits a high color ratio, while low color ratio emissions are found within the collar around the swirl region but still poleward of the main emission. We confirm the apparent strong magnetospheric local time control within the polar collar (Grodent et al., 2003), with the dusk side bright “active region” emissions extending from ~11 to 22 hr of magnetospheric local time. These bright emissions dim by at least an order of magnitude between ~0 and 11 hr magnetospheric local time, in the midnight to dawn side “dark region”. This magnetospheric local time structure holds true even when the entire northern oval is located on the night side of the planet (in ionospheric local time), a geometry unstudied prior to Juno, as it is unobservable from Earth. The swirl region brightens at ionospheric dawn (~5-7 ionospheric local time) and diminishes or completely disappears at ionospheric local times of ~20 to 22 hrs. Finally, the southern auroral polar emissions appear to share all of the local time dependencies of its northern counterpart, but at a reduced intensity.