Search Publications

Electron trapping around a magnetic null
DOI: 10.1029/2008GL034085 Bibcode: 2008GeoRL..3514104H

Escoubet, C. P.; Dandouras, I.; Glassmeier, K. -H. +18 more

Magnetic reconnection is an important process in astrophysical, space and laboratory plasmas. The magnetic null pair structure is theoretically suggested to be a crucial feature of the three-dimensional magnetic reconnection. The physics around the null pair, however, has not been explored in combination with the magnetic field configuration deduc…

2008 Geophysical Research Letters
Cluster 33
Confirmation and utilization of the ``production function'' size-frequency distributions of Martian impact craters
DOI: 10.1029/2007GL031557 Bibcode: 2008GeoRL..35.2205H

Neukum, Gerhard; Werner, Stephanie; Hartmann, William K.

On any planetary surface, impacts of interplanetary bodies create an initial (or ``production function'') size-frequency distribution (SFD) of impact craters. Recent questions have been raised about whether this size distribution can be reliably detected, especially at small sizes. In a test area, we confirm an excellent fit to the distribution we…

2008 Geophysical Research Letters
MEx 32
Behavior of current sheets at directional magnetic discontinuities in the solar wind at 0.72 AU
DOI: 10.1029/2008GL036120 Bibcode: 2008GeoRL..3524102Z

Russell, C. T.; Zhang, T. L.; Glassmeier, K. -H. +10 more

Venus Express interplanetary magnetic field measurements have been examined for magnetic ``holes,'' accompanied by magnetic field directional changes. We examine both the thickness of the current sheet and the depth of the magnetic field depression. We find the thickness of the current sheet is not correlated with the depth of the field depression…

2008 Geophysical Research Letters
VenusExpress 32
Implications from Ithaca Chasma for the thermal and orbital history of Tethys
DOI: 10.1029/2008GL035402 Bibcode: 2008GeoRL..3519203C

Nimmo, F.; Chen, E. M. A.

Flexural modeling of Ithaca Chasma on Tethys suggests that the elastic thickness and the surface heat flux were 5-7 km and 18-30 mW/m2 respectively, when the feature formed (~4 Gyr B.P.). Tidal heating is a plausible heat source, suggesting that Tethys' eccentricity was higher in the past. Depending on Tethys' internal structure, eccent…

2008 Geophysical Research Letters
Cassini 31
Structure of Titan's low altitude ionized layer from the Relaxation Probe onboard HUYGENS
DOI: 10.1029/2008GL035338 Bibcode: 2008GeoRL..3522104L

Berthelier, J. J.; Rodrigo, R.; López-Moreno, J. J. +14 more

Some of the secrets of the atmosphere of Titan have been unveiled by the Huygens Probe. The Permitivity Wave and Altimetry system detected a hidden ionosphere much below the main ionosphere, that lies between 600 and 2000 km. Theoretical models predicted a low altitude ionosphere produced by cosmic rays that, contrary to magnetospheric particles a…

2008 Geophysical Research Letters
Huygens 29
Modulated reconnection rate and energy conversion at the magnetopause under steady IMF conditions
DOI: 10.1029/2007GL032868 Bibcode: 2008GeoRL..35.8104R

Dandouras, I.; Buchert, S.; Vaivads, A. +4 more

We use the multi-spacecraft mission Cluster to make observational estimates of the local energy conversion across the dayside high-latitude magnetopause. The energy conversion is estimated during eleven complete magnetopause crossings under steady south-dawnward interplanetary magnetic field (IMF). We describe a new method to determine the reconne…

2008 Geophysical Research Letters
Cluster 28
Lunar degree 2 potential Love number determination from satellite tracking data
DOI: 10.1029/2007GL031960 Bibcode: 2008GeoRL..35.2204G

Matsumoto, K.; Goossens, S.

The lunar potential Love number k 2 has been determined using available satellite tracking data coming from the Lunar Orbiters I-V, the Apollo 15 and 16 subsatellites, Clementine and Lunar Prospector. Some SMART-1 spacecraft tracking data are also included. A previous determination using spacecraft data reported k 2 = 0.026 +…

2008 Geophysical Research Letters
SMART-1 27
Alfvén vortices in Saturn's magnetosheath: Cassini observations
DOI: 10.1029/2008GL034411 Bibcode: 2008GeoRL..3515102A

Saur, J.; Alexandrova, O.

First signatures of Alfvén vortices in the Kronian magnetosheath are presented. An Alfvén vortex is a non-linear bi-dimensional magnetic structure associated with sheared magnetic field and velocity perturbations, propagating obliquely to the external magnetic field direction. Such structures have been recently discovered by Cluster in Earth's mag…

2008 Geophysical Research Letters
Cassini 27
On the cause of Saturn's plasma periodicity
DOI: 10.1029/2008GL034951 Bibcode: 2008GeoRL..3514105B

André, N.; Coates, A. J.; Dougherty, M. K. +6 more

Periodic plasma enhancements are examined for all Cassini orbits from December 29, 2005 through September 7, 2006. The events, which have UT durations of 3-4 hours, are centered near SLS3 longitude 10° at radial distances near 15 RS and at larger W longitudes at larger distances, reaching 180°W by 49 RS. Magnetic-field data w…

2008 Geophysical Research Letters
Cassini 26
Strong jet and a new thermal wave in Saturn's equatorial stratosphere
DOI: 10.1029/2008GL035515 Bibcode: 2008GeoRL..3523208L

Fletcher, Leigh N.; Achterberg, Richard K.; Flasar, F. Michael +7 more

The strong jet, with a speed between 500 and 600 m/s, is inferred in the equatorial region of Saturn by combining the nadir and limb observations of Composite Infrared Spectrometer (CIRS) aboard the Cassini spacecraft. A similar jet was discovered on Jupiter (F. M. Flasar et al., 2004a). These discoveries raise the possibility that intense jets ar…

2008 Geophysical Research Letters
Cassini 24