Search Publications
Search for Dark Matter Ionization on the Night Side of Jupiter with Cassini
Blanco, Carlos; Leane, Rebecca K.
We present a new search for dark matter (DM) using planetary atmospheres. We point out that annihilating DM in planets can produce ionizing radiation, which can lead to excess production of ionospheric H3+ . We apply this search strategy to the night side of Jupiter near the equator. The night side has zero solar irradiation,…
Cassini spacecraft reveals global energy imbalance of Saturn
West, Robert A.; Nixon, Conor A.; Guillot, Tristan +16 more
The global energy budget is pivotal to understanding planetary evolution and climate behaviors. Assessing the energy budget of giant planets, particularly those with large seasonal cycles, however, remains a challenge without long-term observations. Evolution models of Saturn cannot explain its estimated Bond albedo and internal heat flux, mainly …
A low-density ocean inside Titan inferred from Cassini data
Goossens, Sander; van Noort, Bob; Mateo, Alfonso +2 more
The Cassini mission has provided measurements of the gravity of several moons of Saturn as well as an estimate of the tidal response, which is expressed as the degree 2 Love number k2 of its largest moon, Titan. The first estimates of Titan's Love number were larger than pre-Cassini expectations. Interior modelling suggested it may be e…
A study of Jupiter's UV Great Dark Spot and tropopause to stratosphere winds in the high northern latitudes as seen by Cassini imaging
West, R. A.; Sinclair, J. A.; Del Genio, A. D. +1 more
Images of Jupiter taken during the year 2000 Cassini flyby revealed the early stages and evolution of a high northern-latitude UV Great Dark Spot over a three-month period. They also provided a window on the circulation of Jupiter's polar stratosphere. Jupiter's rarely-detected UV Great Dark Spot (UVGDS) is unusual in several respects. It is an ep…
Modeling Cassini UVIS Interplanetary Hydrogen Lyα Observations from 1999 to 2017
Pryor, Wayne R.; Esposito, Larry W.; Gladstone, G. Randall +3 more
The Cassini Orbiter Ultraviolet Imaging Spectrograph (UVIS) obtained interplanetary hydrogen Lyα observations from 1999 to 2017, with mid-2004 to 2017 observations obtained from Saturn orbit. During its Saturn orbital phase, the spacecraft moved from mostly downwind and sidewind in the heliosphere to upwind. We analyze the full set of observations…
Constraining Time Variations in Enceladus's Water-vapor Plume with Near-infrared Spectra from Cassini's Visual and Infrared Mapping Spectrometer
Hedman, M. M.; Bockelée-Morvan, D.; Capaccioni, F. +2 more
Water vapor produces a series of diagnostic emission lines in the near-infrared between 2.60 and 2.75 µm. The Visual and Infrared Mapping Spectrometer (VIMS) on board the Cassini spacecraft detected this emission signal from Enceladus's plume, and so VIMS observations provide information about the variability of the plume's water-vapor conte…
Surface properties of the seas of Titan as revealed by Cassini mission bistatic radar experiments
Soderblom, Jason M.; Lorenz, Ralph D.; Tortora, Paolo +9 more
Saturn's moon Titan was explored by the Cassini spacecraft from 2004 to 2017. While Cassini revealed a lot about this Earth-like world, its radar observations could only provide limited information about Titan's liquid hydrocarbons seas Kraken, Ligeia and Punga Mare. Here, we show the results of the analysis of the Cassini mission bistatic radar e…
Cassini's CDA observes a variety of dust populations just outside Saturn's main rings
Postberg, Frank; Hillier, Jon K.; Srama, Ralf +5 more
Before the end of its mission, the Cassini spacecraft orbited Saturn in a series of highly inclined elliptical 'Ring-Grazing' orbits (RGO). During the RGO, the spacecraft passed repeatedly through the ring plane outside the F ring, near the orbits of Janus and Epimetheus, at an average relative speed of ~20 km s-1. For the first time, C…
Particle sizes in Saturn's rings from UVIS stellar occultations 2. Outlier Populations in the C ring and Cassini Division
Colwell, J. E.; Esposito, L. W.; Jerousek, R. G. +1 more
The Cassini Ultraviolet Imaging Spectrograph (UVIS) included a High-Speed Photometer (HSP), which observed hundreds of stellar occultations by Saturn's ring system across a range of viewing geometries (Colwell et al. 2010). The unocculted time series data from the HSP follow Poisson counting statistics, such that the second and third central momen…
Cassini UVIS Observations of the Enceladus Auroral Footprint on Saturn in 2017
Pryor, Wayne R.; Magalhães, Fabiola P.; Lamy, Laurent +5 more
Ultraviolet Imaging Spectrograph (UVIS) observations show the Enceladus auroral footprint on Saturn on 2017 September 14, near the end of the Cassini mission. A series of Saturn north polar auroral images were obtained by slowly slewing the Cassini spacecraft at right angles to the UVIS long slit. The images were limb-fit to improve the spacecraft…