Search Publications

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
Electric field variability and classifications of Titan's magnetoplasma environment
DOI: 10.5194/angeo-29-1253-2011 Bibcode: 2011AnGeo..29.1253A

Arridge, C. S.; Achilleos, N.; Guio, P.

The atmosphere of Saturn's largest moon Titan is driven by photochemistry, charged particle precipitation from Saturn's upstream magnetosphere, and presumably by the diffusion of the magnetospheric field into the outer ionosphere, amongst other processes. Ion pickup, controlled by the upstream convection electric field, plays a role in the loss of…

2011 Annales Geophysicae
Cassini 12
Source mechanism of Saturn narrowband emission
DOI: 10.5194/angeo-28-1013-2010 Bibcode: 2010AnGeo..28.1013M

Cecconi, B.; Menietti, J. D.; Rymer, A. M. +2 more

Narrowband emission (NB) is observed at Saturn centered near 5 kHz and 20 kHz and harmonics. This emission appears similar in many ways to Jovian kilometric narrowband emission observed at higher frequencies, and therefore may have a similar source mechanism. Source regions of NB near 20 kHz are believed to be located near density gradients in the…

2010 Annales Geophysicae
Cassini 16
The influence of Titan on Saturn kilometric radiation
DOI: 10.5194/angeo-28-395-2010 Bibcode: 2010AnGeo..28..395M

Cecconi, B.; Ye, S. -Y.; Menietti, J. D. +1 more

Previous studies have shown that the occurrence probability of Saturn Kilometric Radiation (SKR) appears to be influenced by the local time of Titan. Using a more extensive set of data than the original study, we confirm the correlation of higher occurrence probability of SKR when Titan is located near local midnight. In addition, the direction fi…

2010 Annales Geophysicae
Cassini 4
Titan's ionosphere in the magnetosheath: Cassini RPWS results during the T32 flyby
DOI: 10.5194/angeo-27-4257-2009 Bibcode: 2009AnGeo..27.4257G

Gurnett, D. A.; Garnier, P.; Krimigis, S. M. +11 more

The Cassini mission has provided much information about the Titan environment, with numerous low altitude encounters with the moon being always inside the magnetosphere. The only encounter taking place outside the magnetopause, in the magnetosheath, occurred the 13 June 2007 (T32 flyby). This paper is dedicated to the analysis of the Radio and Pla…

2009 Annales Geophysicae
Cassini 26
Titan's plasma environment during a magnetosheath excursion: Real-time scenarios for Cassini's T32 flyby from a hybrid simulation
DOI: 10.5194/angeo-27-669-2009 Bibcode: 2009AnGeo..27..669S

Coates, A. J.; Dougherty, M. K.; Saur, J. +5 more

With a Saturnian magnetopause average stand-off distance of about 21 planetary radii, Titan spends most of its time inside the rotating magnetosphere of its parent planet. However, when Saturn's magnetosphere is compressed due to high solar wind dynamic pressure, Titan can cross Saturn's magnetopause in the subsolar region of its orbit and therefo…

2009 Annales Geophysicae
Cassini 18
Quasiperiodic ULF-pulsations in Saturn's magnetosphere
DOI: 10.5194/angeo-27-885-2009 Bibcode: 2009AnGeo..27..885K

Krupp, N.; Dougherty, M. K.; Glassmeier, K. -H. +2 more

Recent magnetic field investigations made onboard the Cassini spacecraft in the magnetosphere of Saturn show the existence of a variety of ultra low frequency plasma waves. Their frequencies suggest that they are presumably not eigenoscillations of the entire magnetospheric system, but excitations confined to selected regions of the magnetosphere.…

2009 Annales Geophysicae
Cassini 7
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
Plasma and fields in the wake of Rhea: 3-D hybrid simulation and comparison with Cassini data
DOI: 10.5194/angeo-26-619-2008 Bibcode: 2008AnGeo..26..619R

Krupp, N.; Woch, J.; Fränz, M. +7 more

Rhea's magnetospheric interaction is simulated using a three-dimensional, hybrid plasma simulation code, where ions are treated as particles and electrons as a massless, charge-neutralizing fluid. In consistency with Cassini observations, Rhea is modeled as a plasma absorbing obstacle. This leads to the formation of a plasma wake (cavity) behind t…

2008 Annales Geophysicae
Cassini 42
Relationship between solar wind corotating interaction regions and the phasing and intensity of Saturn kilometric radiation bursts
DOI: 10.5194/angeo-26-3641-2008 Bibcode: 2008AnGeo..26.3641B

Cecconi, B.; Lamy, L.; Badman, S. V. +2 more

Voyager spacecraft measurements of Saturn kilometric radiation (SKR) identified two features of these radio emissions: that they pulse at a period close to the planetary rotation period, and that the emitted intensity is correlated with the solar wind dynamic pressure (Desch and Kaiser, 1981; Desch, 1982; Desch and Rucker, 1983). In this study the…

2008 Annales Geophysicae
Cassini 34