Search Publications
Speed of sound measurements and the methane abundance in Titan's atmosphere
Lorenz, R. D.; Hagermann, A.; Leese, M. R. +6 more
Aboard the Huygens probe, which descended through Titan's atmosphere in January 2005, was the Surface Science Package (SSP), a set of 9 sensors, including a speed-of-sound sensor. We present the first detailed description of the SSP speed of sound measurements and report constraints on the methane content in Titan's lower atmosphere based on these…
High spectral resolution UV to near-IR observations of Mars using HST/STIS
Ansty, T. M.; Bell, J. F.
We acquired high spectral and spatial resolution hyperspectral imaging spectrometer observations of Mars from near-UV to near-IR wavelengths (∼300 to 1020 nm) using the STIS instrument on the Hubble Space Telescope during the 1999, 2001, and 2003 oppositions. The data sets have been calibrated to radiance factor ( I/F) and map-projected for compar…
Surface roughness and geological mapping at subhectometer scale from the High Resolution Stereo Camera onboard Mars Express
Greeley, Ronald; Mangold, Nicolas; Martin, Patrick +7 more
The quantitative measurement of surface roughness of planetary surfaces at all scales provides insights into geological processes. A characterization of roughness variations at the scale of a few tens of meters is proposed that complements the analysis of local topographic data of the martian surface at kilometer scale, as achieved from the Mars O…
Constraining the surface properties of Saturn's icy moons, using Cassini/CIRS emissivity spectra
Carvano, J. M.; Barucci, A.; Migliorini, A. +2 more
We have conducted a search for emissivity features in the thermal infrared spectrum of the icy satellites of Saturn, Phoebe, Iapetus, Enceladus, Tethys, and Hyperion, observed by the Composite Infrared Spectrometer (CIRS) on board the Cassini spacecraft. Despite the heterogeneity of the composition of these bodies depicted by Earth-based and Cassi…
MOC observations of four Mars year variations in the south polar residual cap of Mars
Thomas, Peter C.; Wolff, Michael J.; James, Philip B. +1 more
The residual south polar cap of Mars (RSPC) is distinct from the residual north polar cap both in composition and in morphology. CO 2 frost in the RSPC is stabilized by its high albedo during southern spring and summer despite the relatively large insolation during that period. The morphology of the RSPC in summer displays a bewildering…
The H Lyman- α emission line from the upper atmosphere of Jupiter: Parametric radiative transfer study and comparison with data
Clarke, J.; Ben Jaffel, L.; Kim, Y. J.
This study uses the adding-doubling radiative transfer method in which we take into account the curvature effect of the planetary atmosphere in order to test the sensitivity of the jovian Ly- α emission line in relation to H column density, eddy diffusion coefficient, frequency redistribution function for photon scattering, temperature vertical pr…
C ring fine structures revealed in the thermal infrared
Altobelli, N.; Spilker, L.; Pilorz, S. +4 more
We analyze data sets obtained with the Composite Infrared Spectrometer (CIRS) onboard the Cassini spacecraft after the Saturn Orbit Insertion (SOI). Using the mid-IR interferometer's FP3 channel (600-1100 cm -1), we derive radial temperature profiles for the C ring with a spatial resolution never achieved before. For the first time, the…
Submillimeter lightcurves of Vesta
Sykes, Mark V.; Lovell, Amy J.; Chamberlain, Matthew A.
Thermal lightcurves of Asteroid Vesta with significant amplitude have been observed at 870 µm (345 GHz) using the MPIfR 19-channel bolometer of the Heinrich-Hertz Submillimeter Telescope. Shape and albedo are not sufficient to explain the magnitude of this variation, which we relate to global variations in thermal inertia and/or other thermo…
Mass and interior of Enceladus from Cassini data analysis
Iess, Luciano; Anabtawi, Aseel; Tortora, Paolo +4 more
Gravity results are available from radio Doppler data acquired by the Deep Space Network during the encounter of the Cassini spacecraft with Enceladus in February 2005. We report the mass of Enceladus to be (1.0798±0.0016)×10 kg, which implies a density of 1608.9±4 kgm. For a core made of hydrated silicates with a density of 2500 kg m -3
Rotational state of the nucleus of Comet 9P/Tempel 1: Results from Hubble Space Telescope observations in 2004
Weaver, Harold A.; A'Hearn, Michael F.; Toth, Imre +2 more
The nucleus of Comet 9P/Tempel 1 was first observed with the Hubble Space Telescope (HST) in December 1997 [Lamy, P., Toth, I., A'Hearn, M.F., Weaver, H., Weissman, P.R., 2001. Icarus 154, 337-344], but the temporal coverage was insufficient to determine its rotational period. Because the success of the Deep Impact mission was critically dependent…