Rights statement: An edited version of this paper was published by AGU. Copyright 2017 American Geophysical Union. Radioti, A., Grodent, D., Yao, Z. H., Gérard, J.-C., Badman, S. V., Pryor, W., & Bonfond, B. (2017). Dawn auroral breakup at Saturn initiated by auroral arcs: UVIS/Cassini beginning of Grand Finale phase. Journal of Geophysical Research: Space Physics, 122, 12,111–12,119. https://doi.org/10.1002/2017JA024653
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Dawn Auroral Breakup at Saturn Initiated by Auroral Arcs
T2 - UVIS/Cassini Beginning of Grand Finale Phase
AU - Radioti, A.
AU - Grodent, D.
AU - Yao, Z. H.
AU - Gérard, J.-c.
AU - Badman, S. V.
AU - Pryor, W.
AU - Bonfond, B.
N1 - An edited version of this paper was published by AGU. Copyright 2017 American Geophysical Union. Radioti, A., Grodent, D., Yao, Z. H., Gérard, J.-C., Badman, S. V., Pryor, W., & Bonfond, B. (2017). Dawn auroral breakup at Saturn initiated by auroral arcs: UVIS/Cassini beginning of Grand Finale phase. Journal of Geophysical Research: Space Physics, 122, 12,111–12,119. https://doi.org/10.1002/2017JA024653
PY - 2017/12
Y1 - 2017/12
N2 - We present Cassini auroral observations obtained on 11 November 2016 with the Ultraviolet Imaging Spectrograph at the beginning of the F-ring orbits and the Grand Finale phase of the mission. The spacecraft made a close approach to Saturn's southern pole and offered a remarkable view of the dayside and nightside aurora. With this sequence we identify, for the first time, the presence of dusk/midnight arcs, which are azimuthally spread from high to low latitudes, suggesting that their source region extends from the outer to middle/inner magnetosphere. The observed arcs could be auroral manifestations of plasma flows propagating toward the planet from the magnetotail, similar to terrestrial “auroral streamers.” During the sequence the dawn auroral region brightens and expands poleward. We suggest that the dawn auroral breakup results from a combination of plasma instability and global-scale magnetic field reconfiguration, which is initiated by plasma flows propagating toward the planet. Alternatively, the dawn auroral enhancement could be triggered by tail magnetic reconnection.
AB - We present Cassini auroral observations obtained on 11 November 2016 with the Ultraviolet Imaging Spectrograph at the beginning of the F-ring orbits and the Grand Finale phase of the mission. The spacecraft made a close approach to Saturn's southern pole and offered a remarkable view of the dayside and nightside aurora. With this sequence we identify, for the first time, the presence of dusk/midnight arcs, which are azimuthally spread from high to low latitudes, suggesting that their source region extends from the outer to middle/inner magnetosphere. The observed arcs could be auroral manifestations of plasma flows propagating toward the planet from the magnetotail, similar to terrestrial “auroral streamers.” During the sequence the dawn auroral region brightens and expands poleward. We suggest that the dawn auroral breakup results from a combination of plasma instability and global-scale magnetic field reconfiguration, which is initiated by plasma flows propagating toward the planet. Alternatively, the dawn auroral enhancement could be triggered by tail magnetic reconnection.
KW - aurora
KW - Saturn
KW - magnetosphere
U2 - 10.1002/2017JA024653
DO - 10.1002/2017JA024653
M3 - Journal article
VL - 122
SP - 12111
EP - 12119
JO - Journal of Geophysical Research: Space Physics
JF - Journal of Geophysical Research: Space Physics
SN - 2169-9380
IS - 12
ER -