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Topography and geomorphology of the Huygens landing site on Titan
Karkoschka, Erich; Tomasko, Martin G.; Kirk, Randolph L. +16 more
The Descent Imager/Spectral Radiometer (DISR) aboard the Huygens Probe took several hundred visible-light images with its three cameras on approach to the surface of Titan. Several sets of stereo image pairs were collected during the descent. The digital terrain models constructed from those images show rugged topography, in places approaching the…
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…
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…
A new numerical model for the simulation of ELF wave propagation and the computation of eigenmodes in the atmosphere of Titan: Did Huygens observe any Schumann resonance?
Rodrigo, R.; López-Moreno, J. J.; Fulchignoni, M. +18 more
The propagation of extremely low frequency (ELF) electromagnetic waves in the Earth's ionospheric cavity and the associated resonance phenomena have been extensively studied, in relation with lightning activity. We perform a similar investigation for Titan, the largest moon of Saturn. There are important differences between Earth and Titan, as far…
Descent motions of the Huygens probe as measured by the Surface Science Package (SSP): Turbulent evidence for a cloud layer
Zarnecki, John C.; Lorenz, Ralph D.; Leese, Mark R. +5 more
The Huygens probe underwent vigorous short-period motions during its parachute descent through the atmosphere of Saturn's moon Titan in January 2005, at least some of which were excited by the Titan environment. Several sensors in the Huygens Surface Science Package (SSP) detect these motions, indicating the transition to the smaller stabilizer pa…
Near-surface winds at the Huygens site on Titan: Interpretation by means of a general circulation model
Tokano, Tetsuya
This study aims at interpreting the zonal and meridional wind in Titan's troposphere measured by the Huygens probe by means of a general circulation model. The numerical simulation elucidates the relative importance of the seasonal variation in the Hadley circulation and Saturn's gravitational tide in affecting the actual wind profile. The observe…
Huygens’ entry and descent through Titan's atmosphere—Methodology and results of the trajectory reconstruction
Lebreton, Jean-Pierre; Pérez-Ayúcar, Miguel; Sollazzo, Claudio +2 more
The European Space Agency's Huygens probe separated from the NASA Cassini spacecraft on 25 December 2004, after having been attached for a 7-year interplanetary journey and three orbits around Saturn. The probe reached the predefined NASA/ESA interface point on 14 January 2005 at 09:05:52.523 (UTC) and performed a successful entry and descent sequ…
Carbon isotopic enrichment in Titan's tholins? Implications for Titan's aerosols
Szopa, C.; Coll, P.; Raulin, F. +5 more
Since the discovery of the main composition of Titan's atmosphere, many laboratory experiments have been carried out to reproduce its chemical evolution, particularly the formation of organic haze particles found throughout this atmosphere. Some of these simulations have produced solid products - referred to as Titan's tholins - that are assumed t…
Huygens Probe descent dynamics inferred from Channel B signal level measurements
Plettemeier, D.; Bird, M. K.; Edenhofer, P. +3 more
The signal strength of the Huygens Probe Channel B transmission to the Cassini Orbiter was monitored during the Probe descent through Titan's atmosphere on 14 January 2005. A model of the Probe motion during the mission was constructed to include Probe spin, coning motion and tilt caused by varying wind speeds. This simple model is sufficient to r…