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Jupiter's visible aurora and Io footprint

Vasavada, Ashwin R. and Bouchez, Antonin H. and Ingersoll, Andrew P. and Little, Blane and Anger, Clifford D. (1999) Jupiter's visible aurora and Io footprint. Journal of Geophysical Research E, 104 (E11). pp. 27133-27142. ISSN 0148-0227. doi:10.1029/1999JE001055.

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Images obtained by the Galileo spacecraft's solid-state imaging (SSI) system represent the first survey of Jupiter's northern auroral emissions at visible wavelengths and on the nightside of the planet. These images captured the emissions with unprecedented spatial resolutions down to ∼26 km pixel^(−1). Four classes of emission were observed: (1) a continuous, primary arc associated with the middle/outer magnetosphere, (2) a variable secondary arc associated with the region just beyond Io's torus, (3) diffuse “polar cap” emission, and (4) a patch and tail associated with the magnetic footprint of Io. The primary arc emission occurs at an altitude 245±30 km above the 1-bar pressure level. Its horizontal width is typically a few hundred kilometers, and its total optical power output varied between ∼10^(10) and ∼10^(11) W in observations taken months apart. The location of the primary arc in planetary coordinates is similar to that on dayside images at other wavelengths and does not vary with local time. The morphology of the primary arc is not constant, changing from a multiply branched, latitudinally distributed pattern after dusk to a single, narrow arc before dawn. Emission from Io's ionospheric footprint is distinct from both the primary and secondary arcs. Measurements of its optical power output ranged from 2 to 7×10^8 W.

Item Type:Article
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URLURL TypeDescription DOIArticle
Vasavada, Ashwin R.0000-0003-2665-286X
Ingersoll, Andrew P.0000-0002-2035-9198
Additional Information:© 1999 American Geophysical Union. Manuscript Accepted: 13 Jul 1999. Manuscript Received: 1 Apr 1999. We wish to thank two anonymous reviewers, Claudia Alexander, Scott Bolton, John Clarke, Jack Connerney, Renee Prange, Wayne Pryor, Kent Tobiska, and Hunter Waite for exchanging data and ideas. We also thank Herb Breneman, Todd Jones, Dave Senske, and the JPL Multimission Image Processing Lab for the planning and delivery of the Galileo images. Finally, we thank Lisa Crowell for providing us with satellite ephemens data. This work was supported by the Galileo Project, NASA, and NSERC of Canada (B.L ).
Group:UNSPECIFIED, Division of Geological and Planetary Sciences
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Natural Sciences and Engineering Research Council of Canada (NSERC)UNSPECIFIED
Issue or Number:E11
Record Number:CaltechAUTHORS:20130419-133448345
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Official Citation:Vasavada, A. R., A. H. Bouchez, A. P. Ingersoll, B. Little, C. D. Anger, and (1999), Jupiter's visible aurora and Io footprint, J. Geophys. Res., 104(E11), 27133–27142, doi:10.1029/1999JE001055.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:38042
Deposited By: Ruth Sustaita
Deposited On:19 Apr 2013 21:08
Last Modified:09 Nov 2021 23:33

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