Variation of Saturn's UV aurora with SKR phase

[en] It is well known that a wide range of kronian magnetospheric phenomena, including the Saturn kilometric radiation (SKR), exhibit oscillations near the planetary rotation period. However, although the SKR is believed to be generated by unstable auroral electrons, no connection has been established to date between diurnal SKR modulations and UV auroral power. We use an empirical SKR phase determined from Cassini observations to order the 'quiet time' total emitted UV auroral power as observed by the Hubble Space Telescope in programs during the interval 2005-2009. Our results indicate that both the northern and southern UV powers are dependent on SKR phase, varying diurnally by factors of similar to 3. We also show that the UV variation originates principally from the morning half of the oval, consistent with previous observations of the SKR sources. Citation: Nichols, J. D., B. Cecconi, J. T. Clarke, S. W. H. Cowley, J.-C. Gerard, A. Grocott, D. Grodent, L. Lamy, and P. Zarka (2010), Variation of Saturn's UV aurora with SKR phase, Geophys. Res. Lett., 37, L15102, doi: 10.1029/2010GL044057.

Disciplines :

Space science, astronomy & astrophysics

Author, co-author :

Nichols, J. D.

Cecconi, B.

Clarke, J. T.

Cowley, S. W. H.

Gérard, Jean-Claude ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP)

Grocott, A.

Grodent, Denis ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP)

Lamy, L.

Zarka, P.

Language :

English

Title :

Variation of Saturn's UV aurora with SKR phase

Publication date :

2010

Journal title :

Geophysical Research Letters

ISSN :

0094-8276

eISSN :

1944-8007

Publisher :

American Geophysical Union, Washington, United States - District of Columbia

Volume :

Peer reviewed :

Peer Reviewed verified by ORBi

Available on ORBi :

since 10 November 2010

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