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Venus Monitoring Camera for Venus Express
Dierker, C.; Jaumann, R.; Keller, H. U. +28 more
The Venus Express mission will focus on a global investigation of the Venus atmosphere and plasma environment, while additionally measuring some surface properties from orbit. The instruments PFS and SPICAV inherited from the Mars Express mission and VIRTIS from Rosetta form a powerful spectrometric and spectro-imaging payload suite. Venus Monitor…
A review of selected issues concerning the chemistry in Venus’ middle atmosphere
Allen, Mark; Mills, Franklin P.
Even after decades of study using advanced observing instruments and sophisticated numerical models, a number of significant questions remain unanswered concerning the composition and chemistry of Venus' atmosphere. The primary chemical cycles and the interactions among sulfur and chlorine radicals in Venus' middle atmosphere are reviewed to asses…
DISR imaging and the geometry of the descent of the Huygens probe within Titan's atmosphere
Karkoschka, Erich; Schröder, Stefan E.; Tomasko, Martin G. +4 more
The Descent Imager/Spectral Radiometer (DISR) provided 376 images during the descent to Titan and 224 images after landing. Images of the surface had scales between 150 m/pixel and 0.4 mm/pixel, all of which we assembled into a mosaic. The analysis of the surface and haze features in these images and of other data gave tight constraints on the geo…
Photochemical kinetics uncertainties in modeling Titan's atmosphere: First consequences
Dobrijevic, M.; Raulin, F.; Hébrard, E. +1 more
Uncertainties carried by the different kinetic parameters included in photochemical models of planetary atmospheres have rarely been considered even if they are supposed to be contributing mostly to the inconsistencies between observations and computed predictions. In this paper, we report the first detailed analysis of the propagation of uncertai…
Evaluating planetary digital terrain models—The HRSC DTM test
Oberst, J.; Scholten, F.; Neukum, G. +20 more
The High Resolution Stereo Camera (HRSC) has been orbiting the planet Mars since January 2004 onboard the European Space Agency (ESA) Mars Express mission and delivers imagery which is being used for topographic mapping of the planet. The HRSC team has conducted a systematic inter-comparison of different alternatives for the production of high res…
Local plasma processes and enhanced electron densities in the lower ionosphere in magnetic cusp regions on Mars
Gurnett, D. A.; Lundin, R.; Winningham, J. D. +11 more
Both the MARSIS ionospheric sounder and the charged particle instrument package ASPERA-3 are experiments on board the Mars Express spacecraft. Joint observations have shown that events of intense ionospheric electron density enhancements occur in the lower ionosphere of magnetic cusp regions, and that these enhancements are not associated with pre…
Electron conductivity and density profiles derived from the mutual impedance probe measurements performed during the descent of Huygens through the atmosphere of Titan
Berthelier, J. J.; Rodrigo, R.; López-Moreno, J. J. +15 more
During the descent of the Huygens probe through the atmosphere of Titan, on January 14th, 2005, the permittivity, waves and altimetry (PWA) subsystem, a component of the Huygens atmospheric structure instrument (HASI), detected an ionized layer at altitudes around 63 km with two different instruments, the relaxation probe (RP) and the mutual imped…
Physical properties of cometary and interplanetary dust
Lasue, J.; Okada, Y.; Mukai, T. +1 more
In the absence of numerous in situ studies, physical properties of cosmic dust may be derived from observations of their light scattering and thermal properties, through numerical simulations making use of realistic assumptions. Estimations about cometary and interplanetary dust composition, structure, size, as well as about their light scattering…
Solar wind Cluster observations: Turbulent spectrum and role of Hall effect
Alexandrova, O.; Carbone, V.; Veltri, P. +1 more
Turbulent spectrum of magnetic fluctuations in the solar wind nearly follows Kolmogorov's law ∼f below the ion cyclotron frequency fci. Above this frequency, the observed steeper power law is believed to be a 'dissipative range' of the solar wind turbulence. In this paper we analyze magnetic field fluctuations measured onboard Cluster, …
Water vapor mapping on Mars using OMEGA/Mars Express
Bibring, J. -P.; Gondet, B.; Langevin, Y. +8 more
A systematic mapping of water vapor on Mars has been achieved using the imaging spectrometer OMEGA aboard the Mars Express spacecraft, using the depth of the 2.6 µm ( ν1, ν3) band of H 2O. We report results obtained during two periods: (1) Ls=330-40° (January-June 2004), before and after the equinox, and (2) …