Search Publications
A modified “Type I migration” model for propeller moons in Saturn's rings
Tiscareno, Matthew S.
We propose a mechanism for the observed non-keplerian motion (Tiscareno et al., 2010a) of “propeller” moons embedded in Saturn's rings. Our mechanism, in which radial variations in surface density - external to, and unaffected by, the embedded moon - result in an equilibrium semimajor axis for the moon due to “Type I” angular momentum exchange (Cr…
An algorithm for geometric correction of full pass TMC imagery of Chandrayaan-1
Radhadevi, P. V.; Solanki, S. S.; Nagasubramanian, V. +4 more
This paper describes the development of an algorithm for geometric correction of Terrain Mapping Camera (TMC) imagery of Chandrayaan-1 (CH-1). The correction is based on a rigorous sensor model. The algorithm incorporates the camera geometry model, satellite data and lunar control points in a rigorous bundle adjustment updating the satellite model…
Retrieving atmospheric dust opacity on Mars by imaging spectroscopy at large angles
Douté, S.; Ceamanos, X.; Appéré, T.
We propose a new method to retrieve the optical depth of Martian aerosols (AOD) from OMEGA and CRISM hyperspectral imagery at a reference wavelength of 1 µm. Our method works even if the underlying surface is completely made of minerals, corresponding to a low contrast between surface and atmospheric dust, while being observed at a fixed geo…
Multi-resolution digital terrain models and their potential for Mars landing site assessments
Muller, Jan-Peter; Warner, Nicholas H.; Gupta, Sanjeev +2 more
One of the key issues for planetary, especially Mars surface exploration, is how to make an objective assessment of criteria for landing sites selection for future rovers, sample return missions and landers considering topographic variables such as slope, altitude and roughness as well as their physical scattering properties. For these purposes, s…
Operation of CONSERT aboard Rosetta during the descent of Philae
Plettemeier, Dirk; Kofman, Wlodek; Herique, Alain +3 more
This paper presents a study investigating the performance of using the CONSERT instrument aboard the Rosetta spacecraft as a radar sounder during the Separation-Descent-Landing (SDL) phase of the Rosetta mission. Gathering scientifically valuable data during this phase will support CONSERT's primary target, the reconstruction of the 3D permittivit…
Sub-millimeter observations of the terrestrial atmosphere during an Earth flyby of the MIRO sounder on the Rosetta spacecraft
Encrenaz, T.; Lee, S.; Gulkis, S. +5 more
Sub-millimeter spectra recorded by the MIRO sounder aboard the Rosetta spacecraft have been used at the time of an Earth flyby (November 2007) to check the consistency and validity of the instrumental data. High-resolution spectroscopic data were recorded in 8 channels in the vicinity of the strong water line at 557 GHz, and in a broad band contin…
An unnamed fluvial valley system formed under different climates at Xanthe Terra, Mars
Kereszturi, Akos
Analyzing an unnamed fluvial system (at 5.2N 301.4E) in Xanthe Terra on Mars for the first time, the following chronology could be reconstructed. The first period of the fluvial erosion of the area produced channels with higher drainage density than later events, but some resurfacing after this period erased these early, probably interconnected tr…
Model of dust thermal emission of comet 67P/Churyumov-Gerasimenko for the Rosetta/MIRO instrument
Gulkis, Samuel; Bockelée-Morvan, Dominique; Biver, Nicolas +4 more
The ESA's Rosetta spacecraft will arrive at comet 67P/Churyumov-Gerasimenko in 2014. The study of gas and dust emission is primary objective of several instruments on the Rosetta spacecraft, including the Microwave Instrument for the Rosetta Orbiter (MIRO). We developed a model of dust thermal emission to estimate the detectability of dust in the …
The ~10 hour modulation of the relativistic electron spectrum as a result of the periodic motion of the Jovian outer magnetosphere layer: Ulysses observations
Anagnostopoulos, G. C.; Karanikola, I.; Marhavilas, P. K.
We analyze relativistic (E>3 MeV) electron observations during the dayside inbound trajectory of Ulysses (day 33 to day 38, 1992) in the Jovian magnetosphere and we demonstrate that the continuous presence of a relativistic electron layer at higher north latitudes (Ulysses reached ~40° lat. during closest approach the planet). In particular, we…
An overfilled lacustrine system and progradational delta in Jezero crater, Mars: Implications for Noachian climate
Head, James W.; Fassett, Caleb I.; Schon, Samuel C.
The presence of valley networks and open-basin lakes in the late Noachian is cited as evidence for overland flow of liquid water and thus a climate on early Mars that might have supported precipitation and runoff. Outstanding questions center on the nature of such a climate, its duration and variability, and its cause. Open basin lakes, their inte…