Search Publications
Effect of Enceladus's rapid synchronous spin on interpretation of Cassini gravity
McKinnon, William B.
Enceladus's degree 2 gravity, determined by Cassini, is nominally nonhydrostatic to 3σ (J2/C22 = 3.38-3.63, as opposed to 10/3). Iess et al. (2014) interpret this in terms of a hydrostatic interior (core) and isostatic (not hydrostatic) floating ice shell. Enceladus's rapid (1.37 d) synchronous spin and tide distorts its shap…
Possible evidence for a methane source in Enceladus' ocean
Mousis, Olivier; Bouquet, Alexis; Waite, J. Hunter +1 more
The internal ocean of Enceladus can be expected to present conditions favorable to the trapping of volatiles in clathrates. This process could influence the eventual composition of the ocean and therefore of the plumes emitted by the south polar region. Here we used a statistical thermodynamic model to assess which species detected in the plumes b…
Laboratory measurements of cryogenic liquid alkane microwave absorptivity and implications for the composition of Ligeia Mare, Titan
Lorenz, Ralph D.; Lunine, Jonathan I.; Mitchell, Karl L. +2 more
The complex dielectric constants of liquids methane and ethane were measured at 90 K and 14.1 GHz, close to the frequency of the Cassini RADAR. The liquid ethane loss tangent is far greater than that of liquid methane, facilitating discrimination by remote sensing. The results suggest a methane-dominated composition for the northern sea, Ligeia Ma…
Titan's interaction with the supersonic solar wind
Dougherty, M. K.; Kurth, W. S.; Hospodarsky, G. +5 more
9 years in the Saturn system, the Cassini spacecraft finally observed Titan in the supersonic and super-Alfvénic solar wind. These unique observations reveal that Titan's interaction with the solar wind is in many ways similar to unmagnetized planets Mars and Venus and active comets in spite of the differences in the properties of the solar plasma…
The dayside reconnection voltage applied to Saturn's magnetosphere
Masters, A.
The ability of magnetic reconnection between interplanetary and planetary magnetic fields to drive a planetary magnetosphere can be quantified as the resulting voltage applied to the system. We present analytical model predictions of the dayside reconnection voltage at Saturn, a planet where solar wind driving has been the subject of debate. Model…
Saturn's giant storm and global radiant energy
West, Robert A.; Baines, Kevin H.; Nixon, Conor A. +11 more
We analyze the relationship between Saturn's radiant energies and the 2010 giant storm with the Cassini observations. The storm increased the emitted power in a wide latitudinal band (20-55°N) with a maximum change of 9.2 ± 0.1% around 45°N from 2010 to 2011. Such a regional change caused the global-average emitted power to increase by ~2.0 ± 0.2%…
A new upper limit to the field-aligned potential near Titan
Coates, Andrew J.; Waite, J. Hunter; Jones, Geraint H. +1 more
Neutral particles dominate regions of the Saturn magnetosphere and locations near several of Saturn's moons. Sunlight ionizes neutrals, producing photoelectrons with characteristic energy spectra. The Cassini plasma spectrometer electron spectrometer has detected photoelectrons throughout these regions, where photoelectrons may be used as tracers …