Search Publications
Excitation of Saturnian ECH Waves Within Remote Plasma Injections: Cassini Observations
Ni, Binbin; Gu, Xudong; Cao, Xing +7 more
Based on Cassini observations, we report representative electrostatic electron cyclotron harmonic (ECH) wave events observed in Saturn's magnetosphere within remote plasma injections. Unlike local injections, remote injections are "older" injection events that have evolved to form a dispersed signature in particle energy spectrum. We show that Sat…
Tracking the Evolution of an Ocean Within Mimas Using the Herschel Impact Basin
Rhoden, A. R.; Denton, C. A.
Mimas' small size, lack of geologic activity, and high eccentricity suggest a frozen, inactive history. However, Cassini libration measurements are best explained by a present-day liquid ocean under an ice shell 24-31 km thick, a configuration that tidal heating can support. These unexpected findings have motivated further study of Mimas' surface …
Saturn Anomalous Myriametric Radiation, a New Type of Saturn Radio Emission Revealed by Cassini
Jackman, C. M.; Kurth, W. S.; Cecconi, B. +10 more
A new radio component namely Saturn Anomalous Myriametric Radiation (SAM) is reported. A total of 193 SAM events have been identified by using all the Cassini Saturn orbital data. SAM emissions are L-O mode radio emission and occasionally accompanied by a first harmonic in R-X mode. SAM's intensities decrease with increasing distance from Saturn, …
Cassini Observation of Relativistic Electron Butterfly Distributions in Saturn's Inner Radiation Belts: Evidence for Acceleration by Local Processes
Krupp, N.; Wei, Y.; Roussos, E. +3 more
The morphology of electron pitch angle distributions (PADs) helps to identify dynamic processes in Saturn's magnetosphere. Previous studies demonstrated convective transport being important for relativistic electron acceleration at L > 4 in the inner magnetosphere, whereas closer to Saturn the situation is not as well established. We have inves…
The Statistical Morphology of Saturn's Equatorial Energetic Neutral Atom Emission
Mitchell, D. G.; Paranicas, C.; Badman, S. V. +6 more
Saturn's magnetosphere is an efficient emitter of energetic neutral atoms (ENAs), created through charge exchange of energetic ions with the extended neutral cloud originating from the icy moon Enceladus. We present an analysis using the complete image set captured by Cassini's Ion Neutral Camera to characterize Saturn's average ENA morphology. Co…
Titan's Global Radiant Energy Budget During the Cassini Epoch (2004-2017)
West, Robert A.; Nixon, Conor A.; Fry, Patrick M. +5 more
Radiant energies of planets and moons are of wide interest in the fields of geoscience and planetary science. Based on long-term multiinstrument observations from the Cassini spacecraft, we provide here the first observational study of Titan's global radiant energy budget and its seasonal variations. Our results show that Titan's radiant energy bu…
Properties of Plasmoids Observed in Saturn's Dayside and Nightside Magnetodisc
Coates, A. J.; Wei, Y.; Ye, S. -Y. +7 more
Plasmoid is a key structure for transferring magnetic flux and plasma in planetary magnetospheres. At Earth, plasmoids are key media which transfer energy and mass in the "Dungey Cycle." For giant planets, plasmoids are primarily generated by the dynamic processes associated with "Vasyliunas cycle." It is generally believed that planetary magnetot…
The Cushion Region and Dayside Magnetodisc Structure at Saturn
Dougherty, M. K.; Masters, A.; Achilleos, N. +1 more
A sustained quasi dipolar magnetic field between the current sheet outer edge and the magnetopause, known as a cushion region, has previously been observed at Jupiter, but not yet at Saturn. Using the complete Cassini magnetometer data, the first evidence of a cushion region forming at Saturn is shown. Only five examples of a sustained cushion are…
Lower Surface Temperature at Bright Ephemeral Feature Site on Titan's North Pole
Barnes, Jason W.; Dhingra, Rajani D.; Cottini, Valeria +1 more
We report a temperature difference in one of the regions on Titan that is, documented as a bright ephemeral feature (BEF). Spectra were recorded by Cassini's Composite Infrared Spectrometer. BEFs are 5 µm bright areas that appear, disappear, and shift from flyby to flyby at Titan's North Pole observed in Visual and Infrared Mapping Spectrometer (V…
Identifying Active Kelvin-Helmholtz Vortices on Saturn's Magnetopause Boundary
Delamere, P. A.; Johnson, J. R.; Burkholder, B. L. +1 more
For ∼2,000 Cassini magnetopause encounters, we analyse plasma and magnetic fields. The boundary can be unstable to the Kelvin-Helmholtz instability (KHI), which can drive large-scale flows identifiable in plasma measurements. Bulk flow reversed from the expected direction near the magnetopause can indicate vorticity associated with active KH, and …