Please use this identifier to cite or link to this item:
Title: Stability within Jupiter’s polar auroral ‘Swirl Region’ over moderate timescales
Authors: Stallard, Thomas Stephen
Clarke, J. T.
Melin, H.
Miller, S.
Nichols, Jon D.
O'Donoghue, J.
Johnson, Rosie E.
Connerney, J.
Satoh, T.
Perry, Michael
First Published: 5-Jan-2016
Publisher: Elsevier for Academic Press Inc.
Citation: Icarus, 2016, 268, pp. 145-155
Abstract: Jupiter’s Swirl region, poleward of the main auroral emission, has been characterised in previous observations as having highly variable auroral emission, changing dramatically across the region on a two-minute timescale, the typical integration time for UV images. This variability has made comparisons with H3+ emission difficult. Here, we show that the Swirl region in H3+ images is characterised by relatively stable emission, often with an arc of emission on the boundary between the Swirl and Dark regions. Coadding multiple UV images taken over the approximate lifetime of the H3+ molecule in the ionosphere, show similar structures to those observed in the H3+ images. Our analysis shows that UV auroral morphology within Jupiter’s Swirl region is only highly variable on short timescales of ∼100 s, an intrinsic property of the particle precipitation process, but this variability drops away on timescales of 5–15 min. On moderate timescales between 10 and 100 min, the Swirl region is stable, evolving through as yet unknown underlying magnetospheric interactions. This shows that observing the UV aurora over timescales 5–15 min resolves clear auroral structures that will help us understand the magnetospheric origin of these features, and that calculating the variability over different timescales, especially >15 min, provides a new and important new tool in our understanding of Jupiter’s polar aurora.
DOI Link: 10.1016/j.icarus.2015.12.044
ISSN: 0019-1035
Version: Post-print
Status: Peer-reviewed
Type: Journal Article
Rights: Copyright © Elsevier. All rights reserved. This manuscript version is made available after the end of the embargo period under the CC-BY-NC-ND 4.0 license 
Description: The file associated with this record is under a 24-month embargo from publication in accordance with the publisher's self-archiving policy. The full text may be available through the publisher links provided above.
Appears in Collections:Published Articles, Dept. of Physics and Astronomy

Files in This Item:
File Description SizeFormat 
jupiter_polar_stability_final.docPost-review (final submitted)18.54 MBMicrosoft WordView/Open
jupiter_polar_stability_final.pdfPost-review (final submitted)8.81 MBAdobe PDFView/Open

Items in LRA are protected by copyright, with all rights reserved, unless otherwise indicated.