Search Publications

The far-ultraviolet main auroral emission at Jupiter - Part 1: Dawn-dusk brightness asymmetries
DOI: 10.5194/angeo-33-1203-2015 Bibcode: 2015AnGeo..33.1203B

Khurana, K. K.; Badman, S. V.; Bonfond, B. +6 more

The main auroral emission at Jupiter generally appears as a quasi-closed curtain centered around the magnetic pole. This auroral feature, which accounts for approximately half of the total power emitted by the aurorae in the ultraviolet range, is related to corotation enforcement currents in the middle magnetosphere. Early models for these current…

2015 Annales Geophysicae
eHST 26
The far-ultraviolet main auroral emission at Jupiter - Part 2: Vertical emission profile
DOI: 10.5194/angeo-33-1211-2015 Bibcode: 2015AnGeo..33.1211B

Khurana, K. K.; Badman, S. V.; Bonfond, B. +6 more

The aurorae at Jupiter are made up of many different features associated with a variety of generation mechanisms. The main auroral emission, also known as the main oval, is the most prominent of them as it accounts for approximately half of the total power emitted by the aurorae in the ultraviolet range. The energy of the precipitating electrons i…

2015 Annales Geophysicae
eHST 14
Magnetic interconnection of Saturn's polar regions: comparison of modelling results with Hubble Space Telescope UV auroral images
DOI: 10.5194/angeo-31-1447-2013 Bibcode: 2013AnGeo..31.1447B

Belenkaya, E. S.; Cowley, S. W. H.; Kalegaev, V. V. +2 more

We consider the magnetic interconnection of Saturn's northern and southern polar regions controlled by the interplanetary magnetic field (IMF), studying in particular the more complex and interesting case of southward IMF, when the Kronian magnetospheric magnetic field structure is the most twisted. The simpler case of northward IMF is also discus…

2013 Annales Geophysicae
eHST 3
Magnetospheric mapping of the dayside UV auroral oval at Saturn using simultaneous HST images, Cassini IMF data, and a global magnetic field model
DOI: 10.5194/angeo-29-1233-2011 Bibcode: 2011AnGeo..29.1233B

Belenkaya, E. S.; Nichols, J. D.; Cowley, S. W. H. +2 more

We determine the field-aligned mapping of Saturn's auroras into the magnetosphere by combining UV images of the southern dayside oval obtained by the Hubble Space Telescope (HST) with a global model of the magnetospheric magnetic field. The model is tailored to simulate prevailing conditions in the interplanetary medium, corresponding to high sola…

2011 Annales Geophysicae
Cassini eHST 20
Auroral current systems in Saturn's magnetosphere: comparison of theoretical models with Cassini and HST observations
DOI: 10.5194/angeo-26-2613-2008 Bibcode: 2008AnGeo..26.2613C

Coates, A. J.; Dougherty, M. K.; Nichols, J. D. +7 more

The first simultaneous observations of fields and plasmas in Saturn's high-latitude magnetosphere and UV images of the conjugate auroral oval were obtained by the Cassini spacecraft and the Hubble Space Telescope (HST) in January 2007. These data have shown that the southern auroral oval near noon maps to the dayside cusp boundary between open and…

2008 Annales Geophysicae
Cassini eHST 54
Dependence of the open-closed field line boundary in Saturn's ionosphere on both the IMF and solar wind dynamic pressure: comparison with the UV auroral oval observed by the HST
DOI: 10.5194/angeo-26-159-2008 Bibcode: 2008AnGeo..26..159B

Belenkaya, E. S.; Badman, S. V.; Cowley, S. W. H. +2 more

We model the open magnetic field region in Saturn's southern polar ionosphere during two compression regions observed by the Cassini spacecraft upstream of Saturn in January 2004, and compare these with the auroral ovals observed simultaneously in ultraviolet images obtained by the Hubble Space Telescope. The modelling employs the paraboloid model…

2008 Annales Geophysicae
eHST 21
IMF dependence of the open-closed field line boundary in Saturn's ionosphere, and its relation to the UV auroral oval observed by the Hubble Space Telescope
DOI: 10.5194/angeo-25-1215-2007 Bibcode: 2007AnGeo..25.1215B

Alexeev, I. I.; Belenkaya, E. S.; Badman, S. V. +4 more

We study the dependence of Saturn's magnetospheric magnetic field structure on the interplanetary magnetic field (IMF), together with the corresponding variations of the open-closed field line boundary in the ionosphere. Specifically we investigate the interval from 8 to 30 January 2004, when UV images of Saturn's southern aurora were obtained by …

2007 Annales Geophysicae
Cassini eHST 13
A statistical analysis of the location and width of Saturn's southern auroras
DOI: 10.5194/angeo-24-3533-2006 Bibcode: 2006AnGeo..24.3533B

Badman, S. V.; Cowley, S. W. H.; Gérard, J. -C. +1 more

A selection of twenty-two Hubble Space Telescope images of Saturn's ultraviolet auroras obtained during 1997-2004 has been analysed to determine the median location and width of the auroral oval, and their variability. Limitations of coverage restrict the analysis to the southern hemisphere, and to local times from the post-midnight sector to just…

2006 Annales Geophysicae
Cassini eHST 78
HST observations of the inner coma of Comet Levy 1990c.
Bibcode: 1992AnGeo..10..145F

Pasian, F.; Fulle, M.; Benvenuti, P.

Comet Levy 1990c was observed by the Hubble Space Telescope on 27 September 1990, thus allowing to test data reduction procedures which will allow to model the nucleus of future targets of cometary space missions. The authors observe faint hemispherical shells expanding in the coma, which is structured as a sunward fan deflected by solar radiation…

1992 Annales Geophysicae
eHST 3