Search Publications

Cold ionospheric plasma in Titan's magnetotail
DOI: 10.1029/2007GL030701 Bibcode: 2007GeoRL..3424S06W

Russell, C. T.; Wei, H. Y.; Dougherty, M. K. +5 more

The interaction between Titan and the corotating Saturnian plasma forms an induced magnetosphere with an elongated Alfven-wing-style magnetotail. On 26 December 2005, the Cassini spacecraft flew through Titan's magnetotail, providing the first distant tail observation, over 5 Titan radii downstream. We examine measurements observed by the magnetom…

2007 Geophysical Research Letters
Cassini 21
Nondetection of Titan lightning radio emissions with Cassini/RPWS after 35 close Titan flybys
DOI: 10.1029/2007GL031668 Bibcode: 2007GeoRL..3422104F

Gurnett, D. A.; Kurth, W. S.; Fischer, G. +3 more

We report on the nondetection of radio emissions associated with possible lightning flashes in Titan's atmosphere by the Cassini/RPWS (Radio and Plasma Wave Science) instrument. A valid proof for Titan lightning would be the detection of a number of bursty radio signals above Titan's ionospheric cutoff frequency, and they should be grouped near th…

2007 Geophysical Research Letters
Cassini 21
Far plasma wake of Titan from the RPWS observations: A case study
DOI: 10.1029/2007GL030482 Bibcode: 2007GeoRL..3424S04M

Lewis, G. R.; Coates, A. J.; Kurth, W. S. +5 more

The Titan's plasma wake has been investigated using observations from the Radio and Plasma Wave Science (RPWS) instrument onboard the Cassini spacecraft during one Titan flyby on December 26, 2005. The Langmuir Probe and the wideband receiver suggest a strong asymmetry of the plasma wake, which is displaced from the ideal wake. Two distinct struct…

2007 Geophysical Research Letters
Cassini 19
Signatures of Enceladus in Saturn's E ring
DOI: 10.1029/2006GL029120 Bibcode: 2007GeoRL..34.9104J

Morfill, Gregor E.; Horányi, Mihály; Juhász, Antal

Dust production from Enceladus has long been suggested as the main source of dust in Saturn's E ring. This was supported by the observation that the ring's optical depth peaks close to the orbit of this moon. However, both HST and Keck observations indicated that the peak of the optical depth distribution in fact lies outside the orbit of Enceladu…

2007 Geophysical Research Letters
Cassini 19
TC1 and Cluster observation of an FTE on 4 January 2005: A close conjunction
DOI: 10.1029/2006GL028241 Bibcode: 2007GeoRL..34.3106W

Pitout, F.; Wei, Y.; Dandouras, I. +20 more

Observations of a Flux Transfer Event (FTE) signature at the dayside magnetopause are reported, which was consecutively observed on 4 January 2005 by both the Double Star/TC1 spacecraft and the Cluster quartet, while the spacecraft were traversing through the northern-dusk magnetopause. The event occurred as a magnetosheath FTE first at the Cluste…

2007 Geophysical Research Letters
Cluster DoubleStar 18
Contributions to the cross shock electric field at a quasiperpendicular collisionless shock
DOI: 10.1029/2007GL030610 Bibcode: 2007GeoRL..3417104E

Eastwood, J. P.; Bale, S. D.; Mozer, F. S. +1 more

The normal electric field structure of a supercritical (M ms = 5.2), quasiperpendicular (theta Bn = 70°) collisionless shock is examined using Cluster four-spacecraft observations of the terrestrial bow shock. Comparing the observed electric field with magnetic field and plasma observations, two different techniques find that the J × B/ne term in …

2007 Geophysical Research Letters
Cluster 13
Atypical current sheets and plasma bubbles: A self-consistent kinetic model
DOI: 10.1029/2007GL029693 Bibcode: 2007GeoRL..3415101S

Sitnov, M. I.; Swisdak, M.; Guzdar, P. N.

As revealed by CLUSTER observations, thin current sheets in the magnetotail may strongly differ from the conventional Harris profile due to the effects of embedding and bifurcation. At the same time, they often have no signatures of collisionless magnetic reconnection. A universal phenomenon involving such atypical current sheets, which is connect…

2007 Geophysical Research Letters
Cluster 11
Energy input from the exterior cusp into the ionosphere: Correlated ground-based and satellite observations
DOI: 10.1029/2006GL028617 Bibcode: 2007GeoRL..34.4102Y

Fazakerley, A. N.; André, M.; Réme, H. +7 more

The energy transport from the exterior cusp into the ionosphere is investigated using coordinated ground-based (EISCAT and MIRACLE) and satellite (Cluster) observations. EISCAT and MIRACLE data are used to estimate the plasma heating in the F-region and the Joule heating in the E-region. Cluster measurements are used to derive the electromagnetic …

2007 Geophysical Research Letters
Cluster 9
Oscillation of Venus' upper atmosphere
DOI: 10.1029/2007GL029252 Bibcode: 2007GeoRL..34.8202F

Forbes, J. M.; Konopliv, A.

Little is known about the variability of Venus' upper atmosphere. We report discovery of a large (~ +/-30-50%) 9-day period density oscillation, derived from radar tracking of the Magellan spacecraft from 15 Sept 92 - 24 May 93. The densities correspond to 164-184 km altitude, 11°N latitude, and cover all local times. The wave is presumed to propa…

2007 Geophysical Research Letters
VenusExpress 9
Measuring the stress state of the Saturnian magnetosphere
DOI: 10.1029/2007GL029315 Bibcode: 2007GeoRL..3412103L

Russell, C. T.; Dougherty, M. K.; Khurana, K. K. +1 more

The dynamics of a planetary magnetosphere can be quantified by subtracting the system's ``ground'' state from the observed state and tracking their difference. When a magnetosphere is stressed, by external and internal forces, the magnetic field lines become stretched or compressed. In this paper, we construct an index of the stress state of the S…

2007 Geophysical Research Letters
Cassini 6