Search Publications

3D global multi-species Hall-MHD simulation of the Cassini T9 flyby
DOI: 10.1029/2007GL031627 Bibcode: 2007GeoRL..3424S10M

Neubauer, Fritz M.; Russell, Christopher T.; Gombosi, Tamas I. +8 more

The wake region of Titan is an important component of Titan's interaction with its surrounding plasma and therefore a thorough understanding of its formation and structure is of primary interest. The Cassini spacecraft passed through the distant downstream region of Titan on 18:59:30 UT Dec. 26, 2005, which is referred to as the T9 flyby and provi…

2007 Geophysical Research Letters
Cassini 48
Tethys: Lithospheric thickness and heat flux from flexurally supported topography at Ithaca Chasma
DOI: 10.1029/2007GL031467 Bibcode: 2007GeoRL..3421203G

Neukum, Gerhard; Thomas, Peter C.; Helfenstein, Paul +2 more

We have identified flexural uplift along the flanks of Tethys' Ithaca Chasma using Cassini stereo-derived topography. Modeling the topography as a broken elastic plate yields an effective elastic lithospheric thickness in the range of 5-7 km and, combined with the strength envelope of the lithosphere, a mechanical lithospheric thickness of 16-20 k…

2007 Geophysical Research Letters
Cassini 48
SAID: Plasmaspheric short circuit of substorm injections
DOI: 10.1029/2007GL031925 Bibcode: 2007GeoRL..3424101M

Mishin, E. V.; Puhl-Quinn, P. A.

We present magnetically-conjugate Cluster/DMSP observations of subauroral ion drifts (SAID) after the onset of a weak substorm on 18 March 2002 that confirm and expand on the previous Cluster/DMSP results. The outer side of the SAID channel is aligned with the plasmapause and its outer edge marks the dispersionless boundary of the electron precipi…

2007 Geophysical Research Letters
Cluster 46
Source of whistler emissions at the dayside magnetopause
DOI: 10.1029/2006GL029195 Bibcode: 2007GeoRL..34.9106V

André, M.; Stenberg, G.; Vaivads, A. +4 more

Observations of whistler emissions are common in the magnetosphere near the dayside magnetopause. We show that one of the major source regions for these emissions is magnetic field minima that form along magnetic flux tubes at high latitudes. Using multispacecraft Cluster observations we experimentally confirm for the first time the existence of t…

2007 Geophysical Research Letters
Cluster 45
Stability of hydrated minerals on Mars
DOI: 10.1029/2007GL031267 Bibcode: 2007GeoRL..3420202C

Mustard, John F.; Bibring, Jean-Pierre; Poulet, François +7 more

The validity of recent identification of various hydrated minerals (kieserite, gypsum, hexahydrite, nontronite, chamosite, and montmorillonite) on Mars was assessed by exposing these minerals to simulated Martian surface conditions of atmospheric composition and pressure, temperature, and ultraviolet light irradiation. When exposed to such conditi…

2007 Geophysical Research Letters
MEx 45
Titan airglow spectra from Cassini Ultraviolet Imaging Spectrograph (UVIS): EUV analysis
DOI: 10.1029/2007GL031555 Bibcode: 2007GeoRL..3424204A

Stewart, Ian; Gustin, Jacques; Ajello, Joseph M. +7 more

We present the first UV airglow observations of Titan's atmosphere by the Ultraviolet Imaging Spectrograph (UVIS) on Cassini. Using one spectral channel in the EUV from 561-1182 Å and one in the FUV from 1115-1913 Å, UVIS observed the disk on 13 December, 2004 at low solar activity. The EUV spectrum consists of three band systems of N2

2007 Geophysical Research Letters
Cassini 45
Magnetic signatures of plasma-depleted flux tubes in the Saturnian inner magnetosphere
DOI: 10.1029/2007GL030374 Bibcode: 2007GeoRL..3414108A

André, N.; Gurnett, D. A.; Lewis, G. R. +12 more

Initial Cassini observations have revealed evidence for interchanging magnetic flux tubes in the inner Saturnian magnetosphere. Some of the reported flux tubes differ remarkably by their magnetic signatures, having a depressed or enhanced magnetic pressure relative to their surroundings. The ones with stronger fields have been interpreted previous…

2007 Geophysical Research Letters
Cassini 45
A Cluster measurement of fast magnetic reconnection in the magnetotail
DOI: 10.1029/2006GL028006 Bibcode: 2007GeoRL..34.1101X

Escoubet, C. P.; Balogh, A.; Dandouras, I. +11 more

Fast reconnection is crucial to magnetospheric substorms, solar and stellar flares and fusion plasmas. Ultimate confirmation of fast reconnection must be achieved by multi-spacecraft detections of the reconnection rate itself and associated dimensions of the diffusion region. Here we report a multi-spacecraft measurement of fast reconnection rate …

2007 Geophysical Research Letters
Cluster 42
Energetic electrons injected into Saturn's neutral gas cloud
DOI: 10.1029/2006GL028676 Bibcode: 2007GeoRL..34.2109P

Krupp, N.; Krimigis, S. M.; Mitchell, D. G. +7 more

We demonstrate that the population of 20-410 keV electrons observed in Saturn's inner magnetosphere result principally from recent injections. Electrons at these energies appear to survive only up to a few days in the neutral gas cloud emitted by gas jets in Enceladus's southern hemisphere. Ions of similar energies have much shorter lifetimes in t…

2007 Geophysical Research Letters
Cassini 41
Saturn's satellite Rhea is a homogeneous mix of rock and ice
DOI: 10.1029/2006GL028100 Bibcode: 2007GeoRL..34.2202A

Anderson, J. D.; Schubert, G.

A close flyby of Saturn's satellite Rhea by the Cassini spacecraft on 26 November 2005 can be used to infer its mass and quadrupole gravity moments. From these data we derive a mean density of 1233 ± 5 kg m-3 for Rhea and an axial moment of inertia consistent with an undifferentiated interior. The small density implies an interior made up of about…

2007 Geophysical Research Letters
Cassini 41