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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Mechanisms of Saturn's Near-Noon Transient Aurora
T2 - In Situ Evidence From Cassini Measurements
AU - Yao, Z. H.
AU - Radioti, A.
AU - Rae, I. J.
AU - Liu, J.
AU - Grodent, D.
AU - Ray, L. C.
AU - Badman, S. V.
AU - Coates, A. J.
AU - Gérard, J. C.
AU - Waite, J. H.
AU - Yates, J. N.
AU - Shi, Q. Q.
AU - Wei, Y.
AU - Bonfond, B.
AU - Dougherty, M. K.
AU - Roussos, E.
AU - Sergis, N.
AU - Palmaerts, B.
PY - 2017/11/28
Y1 - 2017/11/28
N2 - Although auroral emissions at giant planets have been observed for decades, the physical mechanisms of aurorae at giant planets remain unclear. One key reason is the lack of simultaneous measurements in the magnetosphere while remote sensing of the aurora. We report a dynamic auroral event identified with the Cassini Ultraviolet Imaging Spectrograph (UVIS) at Saturn on 13 July 2008 with coordinated measurements of the magnetic field and plasma in the magnetosphere. The auroral intensification was transient, only lasting for ∼30 min. The magnetic field and plasma are perturbed during the auroral intensification period. We suggest that this intensification was caused by wave mode conversion generated field-aligned currents, and we propose two potential mechanisms for the generation of this plasma wave and the transient auroral intensification. A survey of the Cassini UVIS database reveals that this type of transient auroral intensification is very common (10/11 time sequences, and ∼10% of the total images).
AB - Although auroral emissions at giant planets have been observed for decades, the physical mechanisms of aurorae at giant planets remain unclear. One key reason is the lack of simultaneous measurements in the magnetosphere while remote sensing of the aurora. We report a dynamic auroral event identified with the Cassini Ultraviolet Imaging Spectrograph (UVIS) at Saturn on 13 July 2008 with coordinated measurements of the magnetic field and plasma in the magnetosphere. The auroral intensification was transient, only lasting for ∼30 min. The magnetic field and plasma are perturbed during the auroral intensification period. We suggest that this intensification was caused by wave mode conversion generated field-aligned currents, and we propose two potential mechanisms for the generation of this plasma wave and the transient auroral intensification. A survey of the Cassini UVIS database reveals that this type of transient auroral intensification is very common (10/11 time sequences, and ∼10% of the total images).
KW - Aurora
KW - Cassini
KW - Field-aligned current
KW - Plasma wave
KW - Saturn
U2 - 10.1002/2017GL075108
DO - 10.1002/2017GL075108
M3 - Journal article
VL - 44
SP - 11,217-11,228
JO - Geophysical Research Letters
JF - Geophysical Research Letters
SN - 0094-8276
IS - 22
ER -