In situ and remote observations of the ultraviolet footprint of the moon Callisto by the Juno spacecraft
Jupiter exhibits peculiar multiwavelength auroral emissions resulting from the electromagnetic interactions of Io, Europa, and Ganymede with the magnetospheric plasma flow. Characterizing the faint auroral footprint of the fourth Galilean moon, Callisto, has always been challenging because of its expected weakness and its proximity to Jupiter's bright main aurora. Here, we report on unusual magnetospheric conditions that led to an equatorward shift of Jupiter's main auroral oval unveiling the auroral footprints of the four Galilean moons in a single observation. Remote observations by the Juno spacecraft reveal a double-spot structure, characteristic of the footprints of the other three moons, with a maximum ultraviolet brightness of 137 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo>±</mml:mo></mml:math> 15 kR. Concurrent observations within Callisto's flux tube reveal field-aligned electrons with a characteristic energy of 10 keV, depositing an energy flux of 55 mW.m<sup>-2</sup> in Jupiter's atmosphere. The electron properties are consistent with the triggering of radio emissions with intensities lower than 5 × 10<sup>-18</sup> W.m<sup>-2</sup>.Hz<sup>-1</sup>.
Authors
- Laurent Lamy (ORCID: https://orcid.org/0000-0002-8428-1369)
- Quentin Nénon (ORCID: https://orcid.org/0000-0001-8130-9832)
- P. Louarn (ORCID: https://orcid.org/0000-0003-2783-0808)
- Joshua A. Kammer (ORCID: https://orcid.org/0000-0002-3441-3757)
- F. Allegrini (ORCID: https://orcid.org/0000-0003-0696-4380)
- W. S. Kŭrth (ORCID: https://orcid.org/0000-0002-5471-6202)
- Vincent Hue (ORCID: https://orcid.org/0000-0001-9275-0156)
- Daniel Santos‐Costa (ORCID: https://orcid.org/0000-0003-0384-5255)
- Rohini Giles (ORCID: https://orcid.org/0000-0002-7665-6562)
- A. H. Sulaiman (ORCID: https://orcid.org/0000-0002-0971-5016)
- B. Collet (ORCID: https://orcid.org/0000-0003-1314-9632)
- J. E. P. Connerney (ORCID: https://orcid.org/0000-0001-7478-6462)
- R. W. Ebert (ORCID: https://orcid.org/0000-0002-2504-4320)
- G. R. Gladstone (ORCID: https://orcid.org/0000-0003-0060-072X)
- Bertrand Bonfond (ORCID: https://orcid.org/0000-0002-2514-0187)
- T. K. Greathouse (ORCID: https://orcid.org/0000-0001-6613-5731)
- R. Prangé (ORCID: https://orcid.org/0000-0001-8809-4563)
- P. Zarka (ORCID: https://orcid.org/0000-0003-1672-9878)
- J. Rabia (ORCID: https://orcid.org/0000-0003-1429-9122)
- M. H. Versteeg (ORCID: https://orcid.org/0000-0002-2503-9492)
- Corentin Louis (ORCID: https://orcid.org/0000-0002-9552-8822)
- S. J. Bolton (ORCID: https://orcid.org/0000-0002-9115-0789)
- Nicolás André (ORCID: https://orcid.org/0000-0001-8017-5676)
- A. Kamran (ORCID: https://orcid.org/0000-0003-3736-9680)
- J. R. Szalay (ORCID: https://orcid.org/0000-0003-2685-9801)
- E. Penou
Institutions
- University of Iowa (US)
- Southwest Research Institute (US)
- Centre National de la Recherche Scientifique (FR)
- University of Minnesota (US)
- Goddard Space Flight Center (US)
- University of Liège (BE)
- Université Fédérale de Toulouse Midi-Pyrénées (FR)
- Princeton University (US)
- Université Paris Cité (FR)
- Aix-Marseille Université (FR)
- Sorbonne Université (FR)
- Sorbonne Paris Cité (FR)
- Laboratoire atmosphères, milieux, observations spatiales (FR)
- Institut de Recherche en Astrophysique et Planétologie (FR)
- The University of Texas at San Antonio (US)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-09-01
- DOI
- https://doi.org/10.1038/s41467-025-62520-4
- Citations
- 1
- Primary Topic
- Astro and Planetary Science
- Type
- article
- Field-Weighted Citation Impact
- 1.15
Funders
- National Aeronautics and Space Administration
- Aix-Marseille Université
- Agence Nationale de la Recherche
- Fonds De La Recherche Scientifique - FNRS
- Centre National d’Etudes Spatiales
- Centre National de la Recherche Scientifique