Variation of Saturn's UV aurora with SKR phase
- 6 August 2010
- journal article
- Published by American Geophysical Union (AGU) in Geophysical Research Letters
- Vol. 37 (15)
Abstract
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 ∼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.Keywords
This publication has 18 references indexed in Scilit:
- Saturn's equinoctial aurorasGeophysical Research Letters, 2009
- Recurrent energization of plasma in the midnight-to-dawn quadrant of Saturn's magnetosphere, and its relationship to auroral UV and radio emissionsPlanetary and Space Science, 2009
- Discovery of a north‐south asymmetry in Saturn's radio rotation periodGeophysical Research Letters, 2009
- Periodic tilting of Saturn's plasma sheetGeophysical Research Letters, 2008
- A Saturnian longitude system based on a variable kilometric radiation periodGeophysical Research Letters, 2007
- Cassini observations of planetary‐period magnetic field oscillations in Saturn's magnetosphere: Doppler shifts and phase motionGeophysical Research Letters, 2006
- An Earth-like correspondence between Saturn's auroral features and radio emissionNature, 2005
- An interplanetary shock traced by planetary auroral storms from the Sun to SaturnNature, 2004
- Source location of Saturn's kilometric radiation: The Kelvin‐Helmholtz instability hypothesisJournal of Geophysical Research, 1995
- A theory of the terrestrial kilometric radiationThe Astrophysical Journal, 1979