Search Publications
The case for an ocean-bearing Mimas from tidal heating analysis
Rhoden, Alyssa Rose; Walker, Matthew E.
Cassini measurements of Mimas' physical libration can be explained by either a non-hydrostatic core or a global, liquid water ocean beneath a 24-31 km thick ice shell. An ocean within Mimas would be surprising, given the lack of comparable geologic activity to that observed on other ocean-bearing moons like Europa and Enceladus, and thus has impor…
Polar and mid-latitude vortices and zonal flows on Jupiter and Saturn
Yadav, Rakesh K.; Featherstone, Nicholas A.; Aurnou, Jonathan M. +1 more
Zonal flow on Jupiter and Saturn consists of equatorial super-rotation and alternating East-West jet streams at higher latitudes. Interacting with these zonal flows, numerous vortices occur with various sizes and lifetimes. The Juno mission and Cassini's grand finale have shown that the zonal jets of Jupiter and Saturn extend deeply into their mol…
Modeling the complete set of Cassini's UVIS occultation observations of Enceladus' plume
Esposito, Larry W.; Portyankina, Ganna; Aye, Klaus-Michael +2 more
The Cassini Ultraviolet Imaging Spectrograph (UVIS) observed a plume of water vapor spewing out from the south polar regions of Enceladus via occultations 7 times during the Cassini mission. Five of them yielded spatially resolved data that allowed fits to a set of individually modeled jets. We created a direct simulation Monte Carlo (DSMC) model …
Molecular hydrogen in the upper atmospheres of Saturn and Titan
Strobel, Darrell F.
Molecular hydrogen is the third most abundant species in Titan's atmosphere with a tropospheric/lower stratospheric mole fraction of 0.001 derived from Voyager and Cassini measurements and the major species in Saturn's atmosphere. The motivation for this paper is to explore the hypothesis that the corrected H2 density measurements repor…
Cometary ions detected by the Cassini spacecraft 6.5 au downstream of Comet 153P/Ikeya-Zhang
Jones, G. H.; McComas, D. J.; Smith, E. J. +5 more
During March-April 2002, while between the orbits of Jupiter and Saturn, the Cassini spacecraft detected a significant enhancement in pickup proton flux. The most likely explanation for this enhancement was the addition of protons to the solar wind by the ionization of neutral hydrogen in the corona of comet 153P/Ikeya-Zhang. This comet passed rel…
Sub-field of view surface thermal modeling of Cassini CIRS observations of Rhea during south polar winter
Howett, Carly J. A.; Miles, Georgina; Spencer, John +1 more
Rhea's exosphere is thought to originate from sources of carbon, water ice and other volatiles that arrived at Rhea by bombardment. Its seasonal variability is directly driven by polar surface temperatures allowing surface adsorption, and the persistence of source volatiles require that seasonal temperatures remain sufficiently cold to retain them…
Solar occultation observations of Saturn's rings with Cassini UVIS
Colwell, J. E.; Esposito, L. W.; Becker, T. M. +2 more
The Ultraviolet Imaging Spectrograph (UVIS) instrument onboard the Cassini spacecraft observed 41 solar occultations by Saturn's rings through its extreme ultraviolet (56-118 nm) spectrographic channel. These solar occultations complement the set of stellar occultations measured by the broadband UVIS High Speed Photometer in the far ultraviolet (1…