[en] We present observations of significant dynamics within two UV auroral storms observed on Saturn using the Hubble Space Telescope in April/May 2013. Specifically, we discuss bursts of auroral emission observed at the poleward boundary of a solar wind-induced auroral storm, propagating at ˜330% rigid corotation from near ˜01 h LT toward ˜08 h LT. We suggest that these are indicative of ongoing, bursty reconnection of lobe flux in the magnetotail, providing strong evidence that Saturn's auroral storms are caused by large-scale flux closure. We also discuss the later evolution of a similar storm and show that the emission maps to the trailing region of an energetic neutral atom enhancement. We thus identify the auroral form with the upward field-aligned continuity currents flowing into the associated partial ring current.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Nichols, J. D.; Department of Physics and Astronomy, University of Leicester, Leicester, UK
Badman, S. V.; Department of Physics and Astronomy, University of Leicester, Leicester, UK ; Department of Physics, Lancaster University, Lancaster, UK
Baines, K. H.; Space Science and Engineering Center, University of Wisconsin-Madison, Madison, Wisconsin USA
Brown, R. H.; Lunar and Planetary Lab, University of Arizona, Tucson, Arizona USA
Bunce, E. J.; Department of Physics and Astronomy, University of Leicester, Leicester, UK
Clarke, J. T.; Center for Space Physics, Boston University, Boston, Massachusetts USA
Cowley, S. W. H.; Department of Physics and Astronomy, University of Leicester, Leicester, UK
Crary, F. J.; Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, Boulder, Colorado USA
Dougherty, M. K.; Blackett Laboratory, Imperial College London, London, UK
Gérard, Jean-Claude ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Département d'astrophys., géophysique et océanographie (AGO)
Grocott, A.; Department of Physics and Astronomy, University of Leicester, Leicester, UK ; Department of Physics, Lancaster University, Lancaster, UK
Grodent, Denis ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP)
Kurth, W. S.; Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa USA
Melin, H.; Department of Physics and Astronomy, University of Leicester, Leicester, UK
Mitchell, D. G.; Applied Physics Laboratory, Johns Hopkins University, Laurel, Maryland USA
Pryor, W. R.; Department of Science, Central Arizona College, Coolidge, Arizona USA
Stallard, T. S.; Department of Physics and Astronomy, University of Leicester, Leicester, UK)
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