EPSC Abstracts
Vol. 18, EPSC-DPS2025-980, 2025, updated on 09 Jul 2025
https://doi.org/10.5194/epsc-dps2025-980
EPSC-DPS Joint Meeting 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
A bright path under Juno's footprint
Bertrand Bonfond1, Denis Grodent1, Guillaume Sicorello1, Julie Vinesse1, Linus Head1, Jean-Claude Gérard1, Alessandro Moirano1, Bilal Benmahi2,1, Vincent Hue2, Thomas Greathouse3, Randy Gladstone3, and Rohini Giles3
Bertrand Bonfond et al.
  • 1LPAP, STAR Institute, Université de Liège, Liège, Belgium (b.bonfond@uliege.be)
  • 2Aix-Marseille Université, CNRS, CNES, Institut Origines, LAM, Marseille, France
  • 3Southwest Research Institute, San Antonio, Texas, USA

Juno's UltraViolet Spectrograph captures spectrally resolved images of Jupiter's aurorae by scanning a narrow swath across the planet for every rotation of the spacecraft. A mirror at the entrance of the instrument allows us to aim for specific targets up to 30° away from the spin plane. Following a pre-programmed plan designed for each perijove, the instrument can either stare at a given feature for several spins or create maps as complete as possible by shifting the mirror every few spins. Consequently, Juno-UVS does not look at its own magnetic footprint all the time, complicating direct comparisons with in situ instruments. Here we describe a method to recover brightness profiles as complete and as synchronous as possible along the Juno magnetic footprint track. Some additional data products are also built, such as profile of the color ratio between wavelength ranges unabsorbed by hydrocarbons and absorbed ones. Combined with the emission angle, which we also record, this ratio allows us to derive profiles of the mean energy of precipitating electrons. The electron mean energy, and the energy flux deduced from the UV brightness then allow us to compute profiles of the Hall and Pedersen conductance below Juno’s magnetic footpath. Finally, another time series extracted from the UVS data is the noise rate associated with the radiation (mostly relativistic electrons) penetrating the instrument. We will show how this data product allows us to identify bursts of relativistic electrons above Jupiter's poles and connect them to specific regions of the aurorae and/or of the magnetosphere.

How to cite: Bonfond, B., Grodent, D., Sicorello, G., Vinesse, J., Head, L., Gérard, J.-C., Moirano, A., Benmahi, B., Hue, V., Greathouse, T., Gladstone, R., and Giles, R.: A bright path under Juno's footprint, EPSC-DPS Joint Meeting 2025, Helsinki, Finland, 7–12 Sep 2025, EPSC-DPS2025-980, https://doi.org/10.5194/epsc-dps2025-980, 2025.