Search Publications
Photometric analysis of Asteroid (21) Lutetia from Rosetta-OSIRIS images
Vincent, J. -B.; Masoumzadeh, N.; Li, Jian-Yang +1 more
We analyzed the photometric properties of Asteroid (21) Lutetia based on images captured by Rosetta during its flyby. We utilized the images recorded in the F17 filter (λ = 631.6 nm) of the Wide Angle Camera (WAC) and in the F82 & F22 filters (λ = 649.2 nm) of the Narrow Angle Camera (NAC) of the OSIRIS imaging system onboard the spacecraft. W…
Gas phase dicyanoacetylene (C4N2) on Titan: New experimental and theoretical spectroscopy results applied to Cassini CIRS data
Jolly, A.; Cottini, V.; Irwin, P. +6 more
Dicyanoacetylene has not been observed so far in the gas phase in Titan's atmosphere but this molecule is still on the list of the detected species, on the basis of the correspondence between a solid phase feature measured at 478 cm-1 in the laboratory and a spectral feature observed by Voyager. In this work, the infrared spectrum of ga…
Mineralogical and spectral analysis of Vesta's Gegania and Lucaria quadrangles and comparative analysis of their key features
Longobardo, Andrea; Palomba, Ernesto; Zinzi, Angelo +9 more
This work is aimed at developing and interpreting infrared albedo, pyroxene and OH band depths, and pyroxene band center maps of Vesta's Gegania and Lucaria quadrangles, obtained from data provided by the Visible and InfraRed (VIR) mapper spectrometer on board NASA's Dawn spacecraft.
The Gegania and Lucaria quadrangles span latitudes from 22°…Altitude profiles of O2 on Mars from SPICAM stellar occultations
Sandel, B. R.; Montmessin, F.; Bertaux, J. -L. +5 more
We determine the first altitude profiles of O2 in the important photochemical region below 120 km in the atmosphere of Mars by analyzing Mars Express/SPICAM ultraviolet observations of six occultations of stars by the atmosphere. Over the range of 90-130 km the altitude-averaged mixing ratio of O2 relative to the major consti…
Spatial distribution of ice blocks on Enceladus and implications for their origin and emplacement
Ingersoll, Andrew P.; Ewald, Shawn P.; Helfenstein, Paul +2 more
We have mapped the locations of over 100,000 ice blocks across the south polar region of Saturn's moon Enceladus, thus generating the first quantitative estimates of ice-block number density distribution in relation to major geological features. Ice blocks were manually identified and mapped from twenty of the highest resolution (4-25 m per pixel)…
Episodes of fluvial and volcanic activity in Mangala Valles, Mars
Daubar, Ingrid J.; McEwen, Alfred S.; Hamilton, Christopher W. +1 more
A new mapping-based study of the 900-km-long Mangala Valles outflow system was motivated by the availability of new high-resolution images and continued debates about the roles of water and lava in outflow channels on Mars. This study uses photogeologic analysis, geomorphic surface mapping, cratering statistics, and relative stratigraphy. Results …
Modeling of the energetic ion observations in the vicinity of Rhea and Dione
Dandouras, Iannis; Krupp, Norbert; Roussos, Elias +1 more
During several flybys of the Cassini spacecraft by the saturnian moons Rhea and Dione the energetic particle detector MIMI/LEMMS measured a significant reduction of energetic ion fluxes (20-300 keV) in their vicinity, which is caused by the absorption of those ions at the moon surfaces.
In order to simulate the observed depletion profiles we …Non-detection of post-eclipse changes in Io's Jupiter-facing atmosphere: Evidence for volcanic support?
Tsang, Constantine C. C.; Spencer, John R.; Jessup, Kandis Lea
We present observations of Io's tenuous lower atmosphere on the Jupiter-facing hemisphere at ultraviolet wavelengths, from 2100 to 2250 Å, using the Hubble Space Telescope's Cosmic Origins Spectrometer, during the period immediately after Io emerges from Jupiter eclipse. The density of an atmosphere dominantly controlled by frost sublimation is hi…
First extreme and far ultraviolet spectrum of a Comet Nucleus: Results from 67P/Churyumov-Gerasimenko
Stern, S. A.; Feldman, P. D.; Bertaux, J. -L. +7 more
We used the Alice spectrograph onboard the Rosetta comet orbiter spacecraft to observe the surface of Comet 67P/Churyumov-Gerasimenko in the extreme and far ultraviolet (EUV/FUV) from 700 to 2050 Å in mid-August 2014. These observations were before significant EUV/FUV coma signatures were observed by Alice. The resulting coadded spectrum has high …
A large-scale anomaly in Enceladus' microwave emission
Janssen, Michael; Ries, Paul A.
The Cassini spacecraft flew by Enceladus on 6 November 2011, configured to acquire synthetic aperture RADAR imaging of most of the surface with the RADAR instrument. The pass also recorded microwave thermal emission from most of the surface. We report on global patterns of thermal emission at 2.17 cm based on this data set in the context of additi…