Rights statement: An edited version of this paper was published by AGU. Copyright 2018 American Geophysical Union. Lamy, L., Prangé, R., Tao, C., Kim, T., Badman, S. V., Zarka, P., et al. (2018). Saturn's northern aurorae at solstice from HST observations coordinated with Cassini's grand finale. Geophysical Research Letters, 45, 9353–9362. https://doi.org/10.1029/2018GL078211 To view the published open abstract, go to http://dx.doi.org and enter the DOI.
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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 - Saturn's Northern Aurorae at Solstice From HST Observations Coordinated With Cassini's Grand Finale
AU - Lamy, L.
AU - Prangé, R.
AU - Tao, C.
AU - Kim, T.
AU - Badman, S. V.
AU - Zarka, P.
AU - Cecconi, B.
AU - Kurth, W. S.
AU - Pryor, W.
AU - Bunce, E.
AU - Radioti, A.
N1 - An edited version of this paper was published by AGU. Copyright 2018 American Geophysical Union. Lamy, L., Prangé, R., Tao, C., Kim, T., Badman, S. V., Zarka, P., et al. (2018). Saturn's northern aurorae at solstice from HST observations coordinated with Cassini's grand finale. Geophysical Research Letters, 45, 9353–9362. https://doi.org/10.1029/2018GL078211 To view the published open abstract, go to http://dx.doi.org and enter the DOI.
PY - 2018/9/28
Y1 - 2018/9/28
N2 - Throughout 2017, the Hubble Space Telescope (HST) observed the northern far-ultraviolet aurorae of Saturn at northern solstice, during the Cassini Grand Finale. These conditions provided a complete viewing of the northern auroral region from Earth and a maximal solar illumination, expected to maximize the ionosphere-magnetosphere coupling. We analyze 24 HST images concurrently with Cassini measurements of Saturn's kilometric radiation and solar wind parameters predicted by two magnetohydrodynamic models. The aurorae reveal highly variable components, down to timescales of minutes, radiating 7 to 124 GW. They include a nightside-shifted main oval, unexpectedly frequent and bright cusp emissions, and a dayside low-latitude component. On average, these emissions display a strong local time dependence with two maxima at dawn and premidnight, the latter being newly observed and attributed to nightside injections possibly associated with solstice conditions. These results provide a reference frame to analyze Cassini in situ measurements, whether simultaneous or not.
AB - Throughout 2017, the Hubble Space Telescope (HST) observed the northern far-ultraviolet aurorae of Saturn at northern solstice, during the Cassini Grand Finale. These conditions provided a complete viewing of the northern auroral region from Earth and a maximal solar illumination, expected to maximize the ionosphere-magnetosphere coupling. We analyze 24 HST images concurrently with Cassini measurements of Saturn's kilometric radiation and solar wind parameters predicted by two magnetohydrodynamic models. The aurorae reveal highly variable components, down to timescales of minutes, radiating 7 to 124 GW. They include a nightside-shifted main oval, unexpectedly frequent and bright cusp emissions, and a dayside low-latitude component. On average, these emissions display a strong local time dependence with two maxima at dawn and premidnight, the latter being newly observed and attributed to nightside injections possibly associated with solstice conditions. These results provide a reference frame to analyze Cassini in situ measurements, whether simultaneous or not.
KW - aurora
KW - magnetosphere
KW - radio emissions
KW - Saturn
KW - solar wind
U2 - 10.1029/2018GL078211
DO - 10.1029/2018GL078211
M3 - Journal article
AN - SCOPUS:85052206822
VL - 45
SP - 9353
EP - 9362
JO - Geophysical Research Letters
JF - Geophysical Research Letters
SN - 0094-8276
IS - 18
ER -