Search Publications
Generation of whistler mode emissions in the inner magnetosphere: An event study
Pickett, J. S.; Winningham, D.; Fazakerley, A. N. +8 more
On July 24, 2003, when the Cluster 4 satellite crossed the magnetic equator at about 4.5 RE radial distance on the dusk side (∼15 MLT), whistler wave emissions were observed below the local electron gyrofrequency (fce) in two bands, one band above one-half the gyrofrequency (0.5fce) and the other band below 0.5f
In situ observations of the effect of a solar wind compression on Saturn's magnetotail
Coates, A. J.; Dougherty, M. K.; Jackman, C. M. +4 more
In this paper we explore the dynamic response of Saturn's magnetotail to an episode of solar wind compression that took place while Cassini was sampling Saturn's nightside equatorial magnetosphere in 2006. Following an initial increase in solar wind dynamic pressure the magnetosphere was compressed, but over several subsequent days the flaring of …
Ion transport in Titan's upper atmosphere
Dougherty, M. K.; Wahlund, J. -E.; Ågren, K. +4 more
Based on a combined Cassini data set including Ion Neutral Mass Spectrometer, Radio Plasma Wave Science, and Magnetometer measurements made during nine close encounters of the Cassini spacecraft with Titan, we investigate the electron (or total ion) distribution in the upper ionosphere of the satellite between 1250 and 1600 km. A comparison of the…
Time development of field-aligned currents, potential drops, and plasma associated with an auroral poleward boundary intensification
Goldstein, M. L.; McFadden, J. P.; Mozer, F. S. +5 more
We present a detailed case study of the plasma and fields measured by the Cluster spacecraft fleet at the high-altitude auroral zone (∼3.5 RE) across the plasma sheet boundary layer and into the polar cap. This event, which occurred during quiet geomagnetic conditions (Kp = 1+, AE = 50 nT), is of particular interest in that C…
Magnetospheric period oscillations of Saturn's bow shock
Coates, A. J.; Masters, A.; Andrews, D. J. +2 more
Using magnetic field and plasma electron data from 35 Cassini orbits on which the spacecraft crossed Saturn's magnetopause and bow shock during 2004-2007, we provide first evidence for bow shock oscillations related to oscillations in the magnetic field and plasma inside the magnetosphere near the ∼11 h planetary rotation period, termed here the “…
Ionization sources in Titan's deep ionosphere
Galand, Marina; Yelle, Roger; Coates, Andrew +4 more
We analyze a multi-instrumental data set from four Titan encounters by the Cassini spacecraft to investigate in detail the formation of the ionosphere. The data set includes observations of thermospheric and ionospheric species and suprathermal electrons. A model describing the solar and electron energy deposition is used as an organizing element …
Transport of energetic electrons into Saturn's inner magnetosphere
Krupp, N.; Roussos, E.; Johnson, R. E. +8 more
We present energetic electron data obtained by Cassini's Magnetospheric Imaging Instrument in the inner magnetosphere of Saturn. We find here that inward transport and energization processes are consistent with conservation of the first two adiabatic invariants of motion. We model several injections near local midnight, one injection has a maximum…
Ten years of Hubble Space Telescope observations of the variation of the Jovian satellites' auroral footprint brightness
Nichols, J. D.; Clarke, J. T.; Wannawichian, S.
During the past decade, FUV imaging of Jupiter's auroral region by the Hubble Space Telescope (HST) using two instruments, the Space Telescope Imaging Spectrograph (STIS) and the Advanced Camera for Surveys (ACS), has provided detailed information on the electrodynamic interaction between Io's, Ganymede's, and Europa's atmospheres and plasma in Ju…
Multiple harmonic ULF waves in the plasma sheet boundary layer: Instability analysis
RèMe, H.; Keiling, A.; Walsh, A. P. +5 more
Multiple-harmonic electromagnetic waves in the ULF band have occasionally been observed in Earth's magnetosphere, both near the magnetic equator in the outer plasmasphere and in the plasma sheet boundary layer (PSBL) in Earth's magnetotail. Observations by the Cluster spacecraft of multiple-harmonic electromagnetic waves with fundamental frequency…
Cassini observations of narrowband radio emissions in Saturn's magnetosphere
Gurnett, D. A.; Russell, C. T.; Kurth, W. S. +5 more
The Radio and Plasma Wave Science instrument (RPWS) on board the Cassini spacecraft has detected numerous narrowband radio emissions in Saturn's magnetosphere from September 2005 to May 2007. Typically, the narrowband radio emissions occur after an intensification of Saturn kilometric radiation (SKR) and last for several days. These emissions ofte…