[en] Here, for the first time, temporally coincident and spatially overlapping Cassini VIMS and UVIS observations of Saturn's southern aurora are presented. Ultraviolet auroral H and H[SUB]2[/SUB] emissions from UVIS are compared to infrared H[SUB]3[/SUB][SUP]+[/SUP] emission from VIMS. The auroral emission is structured into three arcs - H, H[SUB]2[/SUB] and H[SUB]3[/SUB][SUP]+[/SUP] are morphologically identical in the bright main auroral oval (˜73°S), but there is an equatorward arc that is seen predominantly in H (˜70°S), and a poleward arc (˜74°S) that is seen mainly in H[SUB]2[/SUB] and H[SUB]3[/SUB][SUP]+[/SUP]. These observations indicate that, for the main auroral oval, UV emission is a good proxy for the infrared H[SUB]3[/SUB][SUP]+[/SUP] morphology (and vice versa), but for emission either poleward or equatorward this is no longer true. Hence, simultaneous UV/IR observations are crucial for completing the picture of how the atmosphere interacts with the magnetosphere.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Melin, H.; Space Environment Technologies, Los Angeles, California, USA) ; AB(Department of Physics and Astronomy, University of Leicester, Leicester, UK) ; AC(Department of Physics and Astronomy, University College London, London, UK) ; AD(Institut d'Astrophysique et de Géophysique, University of Liege, Liege, Belgium) ; AE(Department of Physics, Imperial College London, London, UK) ; AF(Institute of Space and Astronautical Science, JAXA, Sagamihara, Japan) ; AG(Central Arizona College, Coolidge, Arizona, USA) ; AH(Department of Physics and Astronomy, University of Leicester, Leicester, UK) ; AI(Department of Planetary Sciences, University of Arizona, Tucson, Arizona, USA) ; AJ(Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA)
Stallard, T.
Miller, S.
Gustin, Jacques ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Physique des atmosphères et des environnements planétaires
Galand, M.
Badman, S. V.
Pryor, W. R.
O'Donoghue, J.
Brown, R. H.
Baines, K. H.
Language :
English
Title :
Simultaneous Cassini VIMS and UVIS observations of Saturn's southern aurora: Comparing emissions from H, H2 and H3+ at a high spatial resolution
Publication date :
01 August 2011
Journal title :
Geophysical Research Letters
ISSN :
0094-8276
eISSN :
1944-8007
Publisher :
American Geophysical Union, Washington, United States - District of Columbia
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