Search Publications
Potential vorticity structure of Titan's polar vortices from Cassini CIRS observations
Nixon, Conor A.; Irwin, Patrick G. J.; Teanby, Nicholas A. +4 more
The Cassini mission has provided the best opportunity to date to extensively study the seasonal variation in Titan's atmosphere, with observations spanning almost half a Titan year (Ls = 293 - 93 °). An important feature in the Titan middle-atmosphere is the formation of a polar vortex. Observations have shown that an initially well-dev…
Kronoseismology V: A panoply of waves in Saturn's C ring driven by high-order internal planetary oscillations
Nicholson, Philip D.; French, Richard G.; Hedman, Matthew M. +3 more
Saturn's rings act as a system of innumerable test particles that are remarkably sensitive to periodic disturbances in the planet's gravitational field. We identify 15 additional density and bending waves in Saturn's C ring driven by the planet's internal normal mode oscillations. The collective response of the rings to Saturn's oscillations resul…
Evolution of Saturn's north polar color and cloud structure between 2012 and 2017 inferred from Cassini VIMS and ISS observations
Baines, K. H.; Sromovsky, L. A.; Fry, P. M.
Cassini/ISS imagery and Cassini/VIMS spectral imaging observations from 0.35 to 5.12 µm show that Saturn's north polar region (70 °-90 ° N) evolved significantly between 2012 and 2017, with the region poleward of the hexagon changing from dark blue/green to a moderately brighter gold color, except for the inner eye region (88.2 °-90 ° N), wh…
Tropopause and lower stratosphere winds and eddy fluxes on Saturn as seen by Cassini imaging
Del Genio, Anthony D.; Barbara, John M.
An automated cloud feature tracking algorithm is applied to 2004 Cassini Imaging Science Subsystem images of Saturn's southern hemisphere and equatorial region (5°N-70°S) in continuum, methane band, and ultraviolet filters to derive zonal wind profiles and eddy momentum fluxes from the middle troposphere cloud tops to the lower stratosphere. Zonal…
Titan occultations of Orion's belt observed with Cassini/UVIS
Yelle, Roger V.; Koskinen, T. T.; Palmer, M. Y.
On 1 February 2016 Titan occulted the three stars in Orion's belt, as seen from the Casssini spacecraft. The ultraviolet spectrometer on Cassini observed this event with the stars arranged along the instrument's entrance slit. These three stellar occultations probed different latitudes in Titan's northern hemisphere but similar longitudes. The occ…
Asymmetrical meridional expansion of bright clouds from Saturn's 2010 great white storm
Dowling, Timothy E.; Li, Liming; Creecy, Ellen C. +4 more
Saturn's recurring great white storms play an important role in modifying its atmosphere. In 2010, such a storm with clouds encircling the planet occurred in the northern hemisphere. An interesting phenomenon of this storm is that the associated bright clouds expanded asymmetrically with respect to latitude, such that the southern boundary of the …
Sizes of the smallest particles at Saturn's ring edges
Colwell, Joshua E.; Esposito, Larry W.; Becker, Tracy M. +1 more
The Ultraviolet Imaging Spectrograph (UVIS) on the Cassini spacecraft observed 275 ring stellar occultations from July 2004 until August 2017. We use stellar occultation data from the UVIS High Speed Photometer (HSP) to characterize the smallest particles at ring edges by modeling observed diffraction signatures. We identify these signatures as sp…
Constraining the surface properties of Helene
Royer, E.; Howett, C. J. A.
We analyze two sets of observations of Dione's co-orbital satellite Helene taken by Cassini's Composite Infrared Spectrometer (CIRS). The first observation was a CIRS FP3 (600 to 1100 cm-1, 9.1 to 16.7 µm) stare of Helene's trailing hemisphere, where two of the ten FP3 pixels were filled. The daytime surface temperatures derived f…
The Faraday rotation effect in Saturn Kilometric Radiation observed by the CASSINI spacecraft
Lamy, Laurent; Fischer, Georg; Kurth, William S. +7 more
Non-thermal radio emissions from Saturn, known as Saturn Kilometric Radiation (SKR), are analyzed for the Faraday rotation effect detected in Cassini RPWS High Frequency Receiver (HFR) observations. This phenomenon, which mainly affects the lower-frequency part of SKR below 200 kHz, is characterized by a rotation of the semi-major axis of the SKR …
Revisiting magnetospheric CAPS TOF data post Cassini
Wilson, R. J.; Reisenfeld, D. B.; Allen, R. C. +2 more
The Cassini Plasma Spectrometer has a Time-of-Flight sensor capable of separating out the major magnetospheric ions at Saturn of protons, ions with a mass to charge of 2 amu/q, and water group ions (O+, OH+, H2O+ and H3O+), yet until this study a survey of their relative proportions…