Search Publications
Overview of the coordinated ground-based observations of Titan during the Huygens mission
de Pater, Imke; Sicardy, Bruno; Buratti, Bonnie J. +50 more
Coordinated ground-based observations of Titan were performed around or during the Huygens atmospheric probe mission at Titan on 14 January 2005, connecting the momentary in situ observations by the probe with the synoptic coverage provided by continuing ground-based programs. These observations consisted of three different categories: (1) radio t…
Characterization of zonal winds in the stratosphere of Titan with UVES: 2. Observations coordinated with the Huygens Probe entry
Livengood, T.; Kostiuk, T.; Witasse, O. +8 more
The Huygens Probe has successfully entered Titan's atmosphere and landed on its surface on 14 January 2005. With the aim of characterizing the zonal wind flow in Titan's stratosphere close to the time of entry, coordinated observations were carried out at the Very Large Telescope on the nights of 7, 12, 14, and 15 January. As in our previous inves…
Enhanced transport in the polar mesosphere of Jupiter: Evidence from Cassini UVIS helium 584 Å airglow
Parkinson, C. D.; Stewart, A. I. F.; Wong, A. S. +2 more
The eddy diffusion profile (K) in the auroral regions of Jupiter is not well determined. However, because of the intense auroral energy input, eddy mixing is expected to be much more effective and may be responsible for the enhancement of heavy hydrocarbon production in the polar region. In this paper, we estimate the increased eddy mixing in the …
Internal structure of Rhea
Castillo-Rogez, Julie
We model the interior of Rhea on the basis of observational constraints and the results from geodynamical models available in the literature. Ten main types of models are defined, depending on the presence or absence of a high-pressure ice layer (ice II), and the extent of separation of the rock component from the volatiles. The degree-two gravity…
Stratospheric global winds on Titan at the time of Huygens descent
Sonnabend, G.; Kostiuk, T.; Witasse, O. +9 more
Measurements of stratospheric zonal winds on Titan were made in preparation for and during the time of the descent of the Huygens Probe into Titan's atmosphere on 14 January 2005. Fully resolved emission lines from ethane near 11.7 µm were measured on the east, center, and west positions on Titan using the NASA/GSFC Heterodyne Instrument for…
Models of synthetic aperture radar backscattering for bright flows and dark spots on Titan
Paillou, Philippe; Crapeau, Marc; Elachi, Charles +2 more
The synthetic aperture radar (SAR) imaging mode of the Cassini RADAR instrument enables us to map the surface of Titan through its thick atmosphere. The first Cassini close flyby, acquired on 26 October 2004, revealed a complex surface, with areas of low relief and dome-like volcanic constructs, flows, and sinuous channels. In particular, fan-like…
Titan's bright spots: Multiband spectroscopic measurement of surface diversity and hazes
Genzel, R.; Eisenhauer, F.; de Pater, I. +3 more
Spatially resolved near-infrared spectra of Titan, which simultaneously cover two CH4 absorption bands (from 1.45 to 2.45 µm), have been obtained using the SINFONI integral-field spectrometer with adaptive optics at the Very Large Telescope (VLT) of the European Southern Observatory. We observe the enhancement in 2 µm surfac…
Nonequilibrium radiative heat flux modeling for the Huygens entry probe
Magin, T. E.; Caillault, L.; Bourdon, A. +1 more
An electronic collisional-radiative model is proposed to predict the nonequilibrium populations and the radiation of the excited electronic states CN(A, B) and N2(A, B, C) during the entry of the Huygens probe into the atmosphere of Titan. The model is loosely coupled with flow solvers using a Lagrangian method. First, the model was tes…
Titan imagery with Keck adaptive optics during and after probe entry
de Pater, Imke; Brown, Michael E.; Marchis, Franck +6 more
We present adaptive optics data from the Keck telescope, taken while the Huygens probe descended through Titan's atmosphere and on the days following touchdown. No probe entry signal was detected. Our observations span a solar phase angle range from 0.05° up to 0.8°, with the Sun in the west. Contrary to expectations, the east side of Titan's stra…
Bistatic observations of Titan's surface with the Huygens probe radio signal
Lorenz, R. D.; Lebreton, J. -P.; Floury, N. +2 more
Huygens provided an unanticipated bistatic radio scattering experiment from Titan's surface. After a successful entry and descent on Titan, on 14 January 2005, the probe remarkably survived the landing and continued radioing from the surface to the overflying Cassini, until the orbiter set below Titan's local horizon. Here we report high-quality m…