Search Publications
Saturn's Seismic Rotation Revisited
Fuller, Jim; Dewberry, Janosz W.; Mankovich, Christopher R.
Normal mode seismology is a promising means of measuring rotation in gas giant interiors, and ring seismology presents a singular opportunity to do so at Saturn. We calculate Saturn's normal modes of oscillation and zonal gravity field, using nonperturbative methods for normal modes in the rigidly rotating approximation, and perturbative methods f…
The Enigmatic Abundance of Atomic Hydrogen in Saturn's Upper Atmosphere
West, Robert A.; Ballester, Gilda E.; Moses, Julianne I. +5 more
A planet's Lyα emission is sensitive to its thermospheric structure. Here we report joint Hubble Space Telescope and Cassini cross-calibration observations of the Saturn Lyα emission made 2 weeks before the Cassini grand finale. To investigate the long-term Saturn Lyα airglow observed by different ultraviolet instruments, we cross-correlate their …
Temporal Evolution of Titan's Stratospheric Temperatures and Trace Gases from a Two-dimensional Retrieval of Cassini Composite Infrared Spectrometer Data
Achterberg, Richard K.
We use a two-dimensional (2D) radiative transfer model of Titan, which allows the atmospheric structure to vary in both altitude and latitude, to retrieve the spatial distribution of temperature, haze extinction, and C2H2, C2H6, C3H8, CH3C2H, C4H
Updated Radiative Transfer Model for Titan in the Near-infrared Wavelength Range: Validation against Huygens Atmospheric and Surface Measurements and Application to the Cassini/VIMS Observations of the Dragonfly Landing Area
Le Mouélic, S.; Cornet, T.; Rodriguez, S. +13 more
We present an analysis of Titan data acquired by the Cassini Visual and Infrared Mapping Spectrometer (VIMS) at the landing site of the Dragonfly mission, using a new version of our radiative transfer model for Titan, with significant updates for the spectroscopic parameters of atmospheric gases and photochemical aerosols. Our updated radiative tr…
New Insights into Variations in Enceladus Plume Particle Launch Velocities from Cassini-VIMS Spectral Data
Hedman, M. M.; Sharma, H.; Vahidinia, S.
Enceladus's plume consists mainly of a mixture of water vapor and solid ice particles that may originate from a subsurface ocean. The physical processes underlying Enceladus's plume particle dynamics are still being debated, and quantifying the particles' size distribution and launch velocities can help constrain these processes. Cassini's Visual …
Simulating Secondary Electron and Ion Emission from the Cassini Spacecraft in Saturn's Ionosphere
Miyake, Y.; Usui, H.; Johansson, F. L. +3 more
The Cassini spacecraft's Grand Finale flybys through Saturn's ionosphere provided unprecedented insight into the composition and dynamics of the gas giant's upper atmosphere and a novel and complex spacecraft-plasma interaction. In this article, we further study Cassini's interaction with Saturn's ionosphere using three-dimensional particle-in-cel…
Titan's North-South Haze Asymmetry Ratio and Boundary at Visible Wavelengths over the Cassini Mission
Barnes, Jason W.; Lorenz, Ralph D.; Vashist, Aadvik S. +2 more
We document the evolution of the north-south asymmetry (NSA) of Titan's haze albedo during the Cassini mission between 2004 and 2017. We analyze coadded cube images taken at 96 distinct wavelengths between 0.35 and 1.05 µm by the Cassini Visual and Infrared Mapping Spectrometer (VIMS-V) instrument from 14 Titan flybys. Over half of a Titan y…
Erratum: "Temporal Evolution of Titan's Stratospheric Temperatures and Trace Gases from a Two-dimensional Retrieval of Cassini Composite Infrared Spectrometer Data" (2023, PSJ, 4, 140)
Achterberg, Richard K.