Search Publications
Composition of Titan's lower atmosphere and simple surface volatiles as measured by the Cassini-Huygens probe gas chromatograph mass spectrometer experiment
Atreya, S. K.; Lunine, J. I.; Kasprzak, W. T. +7 more
The Cassini-Huygens probe gas chromatograph mass spectrometer (GCMS) determined the composition of the Titan atmosphere from ∼140 km altitude to the surface. After landing, it returned composition data of gases evaporated from the surface. Height profiles of molecular nitrogen (N2), methane (CH4), and molecular hydrogen (H
Methane absorption coefficients for the jovian planets from laboratory, Huygens, and HST data
Karkoschka, Erich; Tomasko, Martin G.
We use 11 data sets of methane transmission measurements within 0.4-5.5 µm wavelength to model the methane transmission for temperature and pressure conditions in the jovian planets. Eight data sets are based on published laboratory measurements. Another two data sets come from two spectrometers onboard the Huygens probe that measured methan…
Stability of methane clathrate hydrates under pressure: Influence on outgassing processes of methane on Titan
Sotin, Christophe; Choukroun, Mathieu; Tobie, Gabriel +1 more
We have conducted high-pressure experiments in the H 2O-CH 4 and H 2O-CH 4-NH 3 systems in order to investigate the stability of methane clathrate hydrates, with an optical sapphire-anvil cell coupled to a Raman spectrometer for sample characterization. The results obtained confirm that three …
Chemical Composition of Icy Satellite Surfaces
Stephan, K.; Carlson, R. W.; McCord, T. B. +4 more
Much of our knowledge of planetary surface composition is derived from remote sensing over the ultraviolet through infrared wavelength ranges. Telescopic observations and, in the past few decades, spacecraft mission observations have led to the discovery of many surface materials, from rock-forming minerals to water ice to exotic volatiles and org…
A 3 km atmospheric boundary layer on Titan indicated by dune spacing and Huygens data
Lorenz, Ralph D.; Radebaugh, Jani; Tokano, Tetsuya +2 more
Some 20% of Titan's surface is covered in large linear dunes that resemble in morphology, size and spacing (1-3 km) those seen on Earth. Although gravity, atmospheric density and sand composition are very different on these two worlds, this coincident size scale suggests that the controlling parameter limiting the growth of giant dunes, namely the…
Titan's native ocean revealed beneath some 45km of ice by a Schumann-like resonance
Sotin, Christophe; Béghin, Christian; Hamelin, Michel
After five years of thorough analysis of data from the Huygens Probe that descended into Titan's atmosphere in January 2005, we report major findings inferred from measurements of low frequency waves and atmospheric conductivity. The data account for the observation of a Schumann-like resonance trapped within Titan's atmospheric cavity. On Earth, …
Kinetic study of a N2-CH4 afterglow plasma for production of N-containing hydrocarbon species of Titan’s atmosphere
Pintassilgo, C. D.; Loureiro, J.
We present the results from a self-consistent kinetic model simulating the afterglow of a flowing microwave discharge in pure N 2 in which CH 4 is introduced in the post-discharge. The simulation is carried out for a discharge operating at 433 MHz, in a tube of 1.9 cm inner radius, at the pressure range 26.6-133 Pa. In the po…
Penetrometry of granular and moist planetary surface materials: Application to the Huygens landing site on Titan
Zarnecki, John C.; Lorenz, Ralph D.; Leese, Mark R. +8 more
The Huygens probe landed on the then unknown surface of Titan in January 2005. A small, protruding penetrometer, part of the Surface Science Package (SSP), was pushed into the surface material measuring the mechanical resistance of the ground as the probe impacted the landing site. We present laboratory penetrometry into room temperature surface a…
Far-infrared opacity sources in Titan’s troposphere reconsidered
Irwin, P. G. J.; Teanby, N. A.; de Kok, R.
We use Cassini far-infrared limb and nadir spectra, together with recent Huygens results, to shed new light on the controversial far-infrared opacity sources in Titan's troposphere. Although a global cloud of large CH 4 ice particles around an altitude of 30 km, together with an increase in tropospheric haze opacity with respect to the …
About the Possible Role of Hydrocarbon Lakes in the Origin of Titan's Noble Gas Atmospheric Depletion
Lunine, J. I.; Cordier, D.; Mousis, O. +4 more
An unexpected feature of Titan's atmosphere is the strong depletion in primordial noble gases revealed by the Gas Chromatograph Mass Spectrometer aboard the Huygens probe during its descent on 2005 January 14. Although several plausible explanations have already been formulated, no definitive response to this issue has yet been found. Here, we inv…