[en] Cassini's mission exploring the Saturn system ended with the Grand Finale, a series of orbits bringing the spacecraft closer to the planet than ever before and providing unique opportunities for observations of the ultraviolet aurorae. This study presents a selection of high-resolution imagery showing the aurorae's small-scale structure in unprecedented detail. We find the main arc to vary between a smooth and a rippled structure, likely indicating quiet and disturbed magnetospheric conditions, respectively. It is usually accompanied by a diffuse and dim outer emission on its equatorward side which appears to be driven by wave scattering of hot electrons from the inner ring current into the loss cone. The duskside is characterized by highly dynamic structures which may be signatures of radial plasma injections. This image set will be the only high-resolution data for the foreseeable future and hence forms an important basis for future auroral research on Saturn
Centre/Unité de recherche :
STAR - Space sciences, Technologies and Astrophysics Research - ULiège
Disciplines :
Aérospatiale, astronomie & astrophysique
Auteur, co-auteur :
Bader, Alexander; Department of Physics, Lancaster University, Lancaster, UK
Cowley, Stanley W.H.; Department of Physics and Astronomy, University ofLeicester, Leicester, UK
Badman, Sarah V.; Department of Physics, Lancaster University, Lancaster, UK
Ray, Licia.C; Department of Physics, Lancaster University, Lancaster, UK
Kinrade, Joe; Department of Physics, Lancaster University, Lancaster, UK
Palmaerts, Benjamin ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP)
Pryor, Wayne R.; Science Department, Central ArizonaCollege, Coolidge, AZ, USA
Langue du document :
Anglais
Titre :
The Morphology of Saturn's Aurorae Observed During the Cassini Grand Finale
Date de publication/diffusion :
2020
Titre du périodique :
Geophysical Research Letters
ISSN :
0094-8276
eISSN :
1944-8007
Maison d'édition :
Wiley, Washington, Etats-Unis - District de Columbia
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