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Composition and origin of the atmosphere of Jupiter - an update, and implications for the extrasolar giant planets
Wong, M. H.; Atreya, S. K.; Owen, T. C. +2 more
New developments have led to this update of the composition and origin of Jupiter's atmosphere that were originally discussed in our Planet. Space Sci. 47 (1999) 1243 paper. Since Jupiter can provide important insight into the atmospheres of extrasolar giant planets (EGP), we also discuss here the possible implications of the first detection of an…
Chemical sources of haze formation in Titan's atmosphere
Atreya, S. K.; Wilson, E. H.
A prominent feature of Titan's atmosphere is a thick haze region that acts as the end product of hydrocarbon and nitrile chemistry. Using a one-dimensional photochemical model, an investigation into the chemical mechanisms responsible for the formation of this haze region is conducted. The model derives profiles for Titan's atmospheric constituent…
Production of gyrating ions from nonlinear wave-particle interaction upstream from the Earth's bow shock: A case study from Cluster-CIS
Lundin, R.; Balogh, A.; Dandouras, I. +14 more
We present observations of E<40 keV/e backstreaming ions measured by the Cluster Ion Spectrometry experiment at 1-2 RE upstream of the bow shock. The ions are simultaneously observed at all three spacecrafts for which CIS measurements are available. The proton distributions are analyzed using 4 s time resolution. They are observed in…
Experimental simulation of Titan's atmosphere: Detection of ammonia and ethylene oxide
Coustenis, A.; Coll, P.; Raulin, F. +1 more
For several years now, an experimental simulation of Titan's atmosphere has been on going at LISA. A cold plasma is established in a gas mixture representative of the atmosphere of the satellite. In these experiments, more than 70 organic compounds have been identified, including the first identification in this type of experimental simulation of …
Cassini RADAR: prospects for Titan surface investigations using the microwave radiometer
Lorenz, Ralph D.; West, Richard D.; Janssen, Michael A. +3 more
The Radar instrument on the Cassini spacecraft can be used in a passive radiometric mode to map the microwave emission from Titan: these will be the first resolved microwave emission measurements of an icy satellite. Observation plans and the theory for their interpretation is presented: these data should be able to provide crude composition maps …
The Earth's quasi-parallel bow shock: Review of observations and perspectives for Cluster
Wilkinson, William P.
Spacecraft crossings of the Earth's quasi-parallel bow shock under typical high Mach number conditions are characterized by the presence of large-amplitude, compressive, low-frequency magnetic pulsations. Thus, instead of the fairly abrupt jump from upstream to downstream states one associates with their quasi-perpendicular counterparts, quasi-par…
Bursty energetic electrons confined in flux ropes in the cusp region
Balogh, A.; Zong, Q. -G.; Daly, P. W. +6 more
Bursty energetic electron events with energies of about 20- 400 keV have been observed in the cusp region when the CLUSTER S/C were travelling outbound on 5 April 2001. These electron events are characterized by strong impulsive increases in the flux whereas energetic ions (>30 keV) show no obvious changes. The enhanced energetic electron flux …
First evidence of IMF control of Jovian magnetospheric boundary locations: Cassini and Galileo magnetic field measurements compared
Kivelson, Margaret G.; Southwood, David J.
The Cassini spacecraft, en route to Saturn, passed close to Jupiter while the Galileo spacecraft was completing its 28th and 29th orbits of Jupiter, thus offering a unique opportunity for direct study of the solar wind-Jovian interaction. Here evidence is given of response of the Jovian magnetopause and bow shock positions to changes of the north-…
Structural analysis of periodic surface waves on the magnetospheric boundary
Roth, M.; De Keyser, J.
In situ observations of the flanks of the magnetospheric boundary (magnetopause and boundary layer) sometimes show periodic surface waves to be present. We propose a straightforward but powerful technique for analyzing such periodic boundary waves. The result of this analysis is a two-dimensional picture of the structure of the wave in a reference…
ISO observations of the giant planets and Titan: what have we learnt?
Encrenaz, Thérèse
Infrared spectroscopic observations of the giant planets and Titan with the Infrared Space Observatory (ISO) have brought a significant contribution to our knowledge of these objects. The main discoveries achieved by ISO are: (1) the first detection of an external oxygen source for all giant planets and Titan; (2) the first detection of new strato…