Search Publications
Jupiter’s shrinking Great Red Spot and steady Oval BA: Velocity measurements with the ‘Advection Corrected Correlation Image Velocimetry’ automated cloud-tracking method
de Pater, Imke; Wong, Michael H.; Marcus, Philip S. +1 more
We show that between 1996 and 2006, the area circumscribed by the high-speed collar of the Great Red Spot (GRS) shrunk by 15%, while the peak velocities within its collar remained constant. This shrinkage indicates a dynamical change in the GRS because the region circumscribed by the collar is nearly coincident with the location of the potential v…
Saturn's Titan: Surface change, ammonia, and implications for atmospheric and tectonic activity
Sotin, C.; Baines, K. H.; Clark, R. N. +26 more
Titan is known to have a young surface. Here we present evidence from the Cassini Visual and Infrared Mapping Spectrometer that it is currently geologically active. We report that changes in the near-infrared reflectance of a 73,000 km 2 area on Titan (latitude 26° S, longitude 78° W) occurred between July 2004 and March of 2006. The re…
The geology of Hotei Regio, Titan: Correlation of Cassini VIMS and RADAR
Nicholson, Philip D.; Sotin, Christophe; Barnes, Jason W. +10 more
Joint Cassini VIMS and RADAR SAR data of ∼700-km-wide Hotei Regio reveal a rich collection of geological features that correlate between the two sets of images. The degree of correlation is greater than anywhere else seen on Titan. Central to Hotei Regio is a basin filled with cryovolcanic flows that are anomalously bright in VIMS data (in particu…
Titan's hydrodynamically escaping atmosphere: Escape rates and the structure of the exobase region
Strobel, Darrell F.
In Strobel [Strobel, D.F., 2008. Icarus, 193, 588-594] a mass loss rate from Titan's upper atmosphere, ∼4.5×10 amus, was calculated for a single constituent, N 2 atmosphere by hydrodynamic escape as a high density, slow outward expansion driven principally by solar UV heating due to CH 4 absorption. It was estimated, but not …
The impact of methane thermodynamics on seasonal convection and circulation in a model Titan atmosphere
Mitchell, Jonathan L.; Pierrehumbert, Raymond T.; Frierson, Dargan M. W. +1 more
We identify mechanisms controlling the distribution of methane convection and large-scale circulation in a simplified, axisymmetric model atmosphere of Titan forced by gray radiation and moist (methane) convection. The large-scale overturning circulation, or Hadley cell, is global in latitudinal extent and provides fundamental control of precipita…
Photometric anomalies of the lunar surface studied with SMART-1 AMIE data
Foing, B.; Kreslavsky, M.; Pinet, P. +6 more
We present new results from the mapping of lunar photometric function parameters using images acquired by the spacecraft SMART-1 (European Space Agency). The source data for selected lunar areas imaged by the AMIE camera of SMART-1 and the data processing are described. We interpret the behavior of photometric function in terms of lunar regolith p…
The colors of cometary nuclei—Comparison with other primitive bodies of the Solar System and implications for their origin
Lamy, P.; Toth, I.
We present new color results of cometary nuclei obtained with the Hubble Space Telescope (HST) whose superior resolution enables us to accurately isolate the nucleus signals from the surrounding comae. By combining with scrutinized available data obtained with ground-based telescopes, we accumulated a sample of 51 cometary nuclei, 44 ecliptic come…
The jovian anticyclone BA. II. Circulation and interaction with the zonal jets
Hueso, R.; Sánchez-Lavega, A.; García-Melendo, E. +2 more
In this second part of our study of the large jovian anticyclone BA we present detailed measurements of its internal circulation and numerical models of its interaction with the zonal jets and nearby cyclonic regions. We characterized the flow using high-resolution observations obtained by the Cassini spacecraft in December 2000 (9 months after th…
Mapping of water frost and ice at low latitudes on Mars
Bibring, J. -P.; Bellucci, G.; D'Aversa, E. +2 more
This paper reports on mapping of water frost and ice on Mars, in the range of latitudes between 30°S and 30°N. The study has been carried out by analysing 2485 orbits acquired during almost one martian year by the Mars Express/OMEGA imaging spectrometer. Water frost/ice is identified by the presence of ∼1.5 µm, ∼2 µm and ∼3.0 µm …
Recent rheologic processes on dark polar dunes of Mars: Driven by interfacial water?
Möhlmann, D.; Kereszturi, A.; Berczi, Sz. +4 more
In springtime on HiRISE images of the Southern polar terrain of Mars flow-like or rheologic features were observed. Their dark color is interpreted as partly defrosted surface where the temperature is too high for CO 2 but low enough for H 2O ice to be present there. These branching streaks grow in size and can move by an ave…