Search Publications
Saturn's neutral torus versus Jupiter's plasma torus
Delamere, P. A.; Bagenal, F.; Ray, L. C. +1 more
With the recent discovery of an atmospheric plume of H2O it is thought that Enceladus could deliver as much as 300 kg/s of neutral gas to Saturn's inner magnetosphere. Io is the source of roughly 1 ton/s of sulfur and oxygen gas at Jupiter. Despite the apparent similarity, the neutral/ion ratio at Saturn is 3 orders of magnitude higher …
Magnetosheath plasma expansion: Hybrid simulations
Hellinger, Petr; Dandouras, Iannis; Escoubet, C. Philippe +3 more
We investigate the effect of slow expansion on a magnetosheath plasma and low-frequency waves using a two-dimensional hybrid expanding box simulation. We start our simulation with a homogeneous high beta plasma, which is marginally stable to the mirror and proton cyclotron instabilities. The expansion is imposed as an external force: the physical …
Numerical modeling of the magnetic topology near Mars auroral observations
Barabash, S.; Lundin, R.; Winningham, J. D. +6 more
Magnetohydrodynamic (MHD) simulations of the Mars magnetic field topology are presented for the auroral observations reported from the Mars Express SPICAM instrument. It is found that the field lines closest to the assumed emission location are open. That is, they are connected to the interplanetary magnetic field, thus allowing access for solar w…
Charged particle environment of Titan during the T9 flyby
Coates, A. J.; Crary, F.; Sittler, E. C. +6 more
The ion measurements of the Cassini Plasma Spectrometer are presented which were acquired on 26 December 2005, during the T9 flyby at Titan. The plasma flow and magnetic field directions in the distant plasma environment of the moon were distinctly different from the other flybys. The near-Titan environment, dominated by ions of Titan origin, had …
High resolution mapping of TiO2 abundances on the Moon using the Hubble Space Telescope
Pieters, C. M.; Ulmer, M. P.; Bell, J. F. +4 more
Samples of the lunar regolith returned by Apollo astronauts show large variations (0 to >10 wt%) in TiO2 abundance indicating complex compositional zonation within the lunar mantle. A long held goal of the lunar science community is the accurate determination of TiO2 abundances on the lunar surface through remote sensing m…
Are plasma depletions in Saturn's ionosphere a signature of time-dependent water input?
Moore, Luke; Mendillo, Michael
Recent radio occultation measurements by the Cassini spacecraft reveal the presence of numerous ``ionospheric holes'', or plasma depletions, in Saturn's upper atmosphere that cannot be explained with standard photochemical theory. The holes are remarkably similar in size and shape to artificially-created depletions first observed in the terrestria…
Hybrid simulation of Titan's magnetic field signature during the Cassini T9 flyby
Dougherty, M. K.; Glassmeier, K. -H.; Bertucci, C. +6 more
Titan's induced magnetotail is analyzed in terms of a three-dimensional hybrid model, treating the electrons as a massless, charge-neutralizing fluid, whereas a completely kinetic approach is used to cover ion dynamics. Since during the T9 flyby of Cassini, the spacecraft passed through Titan's induced magnetotail in a distance of about 4 Titan ra…
Structure of Titan's mid-range magnetic tail: Cassini magnetometer observations during the T9 flyby
Coates, A. J.; Dougherty, M. K.; Kurth, W. S. +5 more
We analyze the magnetic structure of Titan's mid-range magnetic tail (5-6 Titan radii downstream from the moon) during Cassini's T9 flyby. Cassini magnetometer (MAG) measurements reveal a well-defined, induced magnetic tail consisting of two lobes and a distinct central current sheet. MAG observations also indicate that Saturn's background magneti…
Internal structure of a magnetic flux rope from Cluster observations
Zong, Q. -G.; Kistler, L. M.; Dunlop, M. W. +3 more
We investigate a magnetic flux rope (MFR) observed by Cluster in the magnetotail during a substorm on 2001 August 22. The MFR was aligned with its principal axis closely along the dawn-dusk direction and had a small size of ~2 R E with a total current of ~0.8 MA. The four spacecraft traversed the MFR at different distances from its cent…
Morphology of the magnetic field near Titan: Hybrid model study of the Cassini T9 flyby
Kallio, E.; Janhunen, P.; Bertucci, C. +4 more
We study the deformation and morphology of the magnetic field near Titan by a three-dimensional numerical quasi-neutral hybrid model (HYB-Titan). We analyze two runs, one in which the sub-rotating plasma consists of oxygen (O+) ions and protons (H+) and another with only protons. We find that both cases result in the generati…