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Cassini observations of flow-like features in western Tui Regio, Titan
Sotin, Christophe; Barnes, Jason W.; Rodriguez, Sebastien +9 more
A large (>3 × 104 km2), lobate, 5-µm-bright region seen by Cassini on Titan's leading equatorial region is best explained as a flow field. We discuss observations from the Visual and Infrared Mapping Spectrometer and Imaging Science Subsystem of the feature and present a map of the field. We establish relative ages o…
Ion cyclotron waves in Saturn's E ring: Initial Cassini observations
Russell, C. T.; Dougherty, M. K.; Leisner, J. S. +3 more
The magnetometer onboard the Cassini spacecraft observes ion cyclotron waves produced by both water-group (O+, OH+, H2O+, or H3O+) and O2+ ions at nearly all radial distances and local times within the E ring. These left-hand elliptically polarized waves travel…
Preliminary interpretation of Titan plasma interaction as observed by the Cassini Plasma Spectrometer: Comparisons with Voyager 1
Coates, A. J.; Crary, F.; Johnson, R. E. +15 more
The Cassini Plasma Spectrometer (CAPS) instrument observed the plasma environment at Titan during the Cassini orbiter's TA encounter on October 26, 2004. Titan was in Saturn's magnetosphere during the Voyager 1 flyby and also during the TA encounter. CAPS measurements from this encounter are compared with measurements made by the Voyager 1 Plasma …
A simple scale height model of the electron density in Saturn's plasma disk
Gurnett, D. A.; Persoon, A. M.; Kurth, W. S. +1 more
A study of electron densities in Saturn's inner magnetosphere is presented using measurements of the upper hybrid resonance frequency obtained from the Radio and Plasma Wave Science (RPWS) instrument on the Cassini spacecraft. The study uses data from the first 16 months of operation in orbit around Saturn. The distribution of density data spans l…
Heliospheric magnetic field polarity inversions driven by radial velocity field structures
Landi, Simone; Hellinger, Petr; Velli, Marco
Magnetic field polarity inversions embedded in the predominantly unipolar fast solar wind have been observed by the Ulysses spacecraft at high latitudes. Such reversals have the nature of folded back field lines which we suggest are generated by the interaction of standard large amplitude, low frequency, Alfvénic turbulence with velocity shears in…
Do BBFs contribute to inner magnetosphere dipolarizations: Concurrent Cluster and Double Star observations
Zhang, T. L.; Klecker, B.; Nakamura, R. +7 more
We examined the relationship between bursty bulk flow (BBF) events observed by Cluster between -19 RE < X < -12 RE and dipolarization events observed by Double Star TC1 between -13 RE < X < -6 RE. TC1 observed dipolarizations for ~33% of the cases when BBFs were observed by Cluster. During th…
Ulysses observations of very different heliospheric structure during the declining phase of solar activity cycle 23
McComas, D. J.; Gosling, J. T.; Elliott, H. A. +1 more
This study examines the most recent observations from the solar wind experiment (SWOOPS) on the Ulysses spacecraft. In contrast to observations over the same locations in the declining phase of the previous solar activity cycle, these data show a more complicated heliospheric structure. Around the start of 2003, a band of slow solar wind resided a…
Electron temperature of Titan's sunlit ionosphere
Coates, A. J.; Wahlund, J. -E.; Galand, M. +2 more
Titan's upper atmosphere is ionized by solar radiation and particle bombardment from Saturn's magnetosphere. The induced ionosphere plays a key role in the coupling of Titan's atmosphere with the Kronian environment. It also provides unique signatures for identifying energy sources upon Titan's upper atmosphere. Here we focus on observations from …
Low-energy (order 10 eV) ion flow in the magnetotail lobes inferred from spacecraft wake observations
Dandouras, I.; André, M.; Quinn, J. +4 more
Cold ionospheric ions with eV energies are common in the magnetosphere and can travel far out in the magnetotail. However, they are difficult to measure with conventional ion spectrometers mounted on spacecraft, since the potential of a sunlit spacecraft often reaches several tens of volts. In this paper we present two alternative methods of measu…
Cassini observations of planetary-period oscillations of Saturn's magnetopause
André, N.; Lewis, G. R.; Coates, A. J. +8 more
Examination of Cassini magnetic field and plasma data in the outer boundary regions of Saturn's magnetosphere shows that magnetopause oscillations at the planetary period commonly occur, in phase with plasma pressure variations inside the magnetosphere. The peak-to-trough amplitude of the boundary oscillations mapped to the planet-Sun line is esti…