Related papers: Implications from secondary emission from neutral …
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…
The ionosphere of Titan hosts a complex ion chemistry leading to the formation of organic dust below 1200 km. Current models cannot fully explain the observed electron temperature in this dusty environment. To achieve new insight, we have…
A surprising and unexpected phenomenon observed during Cassini's Grand Finale was the spacecraft charging to positive potentials in Saturn's ionosphere. Here, the ionospheric plasma was depleted of free electrons with negatively charged…
Current models of Titan ionosphere have difficulties in explaining the observed electron density and/or temperature. In order to get new insights, we re-analyzed the data taken in the ionosphere of Titan by the Cassini Langmuir probe (LP),…
The Cassini spacecraft's last orbits directly sampled Saturn's thermosphere and revealed a much more chemically complex environment than previously believed. Observations from the Ion and Neutral Mass Spectrometer (INMS) aboard Cassini…
Accurate determination of Cassini's spacecraft potential in Titan's ionosphere is important for interpreting measurements by its low energy plasma instruments. Estimates of the floating potential varied significantly, however, between the…
The detection of O2+ and O+ ions over Saturn's main rings by the Cassini INMS and CAPS instruments at Saturn orbit insertion (SOI) in 2004 confirmed the existence of the ring atmosphere and ionosphere. The source mechanism was suggested to…
Saturn's ionosphere is produced when the otherwise neutral atmosphere is exposed to a flow of energetic charged particles or solar radiation. At low latitudes the latter should result in a weak planet-wide glow in infrared (IR),…
During the Grand Finale stage of the Cassini mission, organic-rich ring material was discovered to be flowing into Saturn's equatorial upper atmosphere at a surprisingly large rate. Through a series of photochemical models, we have examined…
The Cassini Plasma Spectrometer (CAPS) Electron Spectrometer (ELS) instrument onboard Cassini revealed an unexpected abundance of negative ions above 950 km in Titan's ionosphere. \textit{In situ} measurements indicated the presence of…
This chapter summarizes our current understanding of the ionosphere of Saturn. We give an overview of Saturn ionospheric science from the Voyager era to the present, with a focus on the wealth of new data and discoveries enabled by Cassini,…
A significant difference in Titan's ionospheric electron density is observed between the T118 and T119 Cassini nightside flybys. These flybys had similar geometry, occurred at the same Saturn local time and while Titan was exposed to…
The Cassini Mission has greatly improved our understanding of the dynamics and chemical processes occurring in Titan's atmosphere. It has also provided us with more insight into the formation of the aerosols in the upper atmospheric layers.…
We analyze data from the final two years of the Cassini mission to retrieve the distributions of methane, ethane, acetylene, ethylene, and benzene in Saturn's upper stratosphere and mesosphere from stellar occultations observed by the…
Titan's ionosphere contains a plethora of hydrocarbons and nitrile cations and anions as measured by the Ion Neutral Mass Spectrometer and Cassini Plasma Spectrometer (CAPS) onboard the Cassini spacecraft. Data from the CAPS Ion Beam…
A planet's Lyman-{\alpha} (Ly{\alpha}) emission is sensitive to its thermospheric structure. Here, we report joint Hubble Space Telescope (HST) and Cassini cross-calibration observations of the Saturn Ly{\alpha} emission made two weeks…
We construct Saturn equatorial neutral temperature and density profiles of H, H$_2$, He, and CH$_4$, between 10$^{-12}$ and 1 bar using measurements from Cassini's Ion Neutral Mass Spectrometer (INMS) taken during the spacecraft's final…
Observations with Cassini's Electron Spectrometer discovered negative ions in Titan's ionosphere, at altitudes between 1400 and 950 km. Within the broad mass distribution extending up to several thousand amu, two distinct peaks were…
We examine Saturn's non-auroral (dayglow) emissions at Lyman-$\alpha$ observed by the {Cassini/UVIS} instrument from 2004 until 2016, to constrain meridional and seasonal trends in the upper atmosphere. We separate viewing geometry effects…
The lightning activity in Saturn's atmosphere has been monitored by Cassini for more than six years. The continuous observations of the radio signatures called SEDs (Saturn Electrostatic Discharges) combine favorably with imaging…