Search Publications
Summer Evolution of the North Polar Cap of Mars as Observed by OMEGA/Mars Express
Bibring, J. -P.; Gondet, B.; Langevin, Y. +3 more
The Observatoire pour la Minéralogie, l'Eau, les Glaces, et l'Activité (OMEGA) visible-infrared imaging spectrometer extensively observed regions of Mars with latitudes above 70°N in late 2004 (heliocentric longitude from Ls 93° to Ls 127°). The extent of water ice at the surface and the size of ice grains were monitored as a…
Dynamics of Saturn's Magnetosphere from MIMI During Cassini's Orbital Insertion
Livi, S.; Hsieh, K. C.; Krupp, N. +29 more
The Magnetospheric Imaging Instrument (MIMI) onboard the Cassini spacecraft observed the saturnian magnetosphere from January 2004 until Saturn orbit insertion (SOI) on 1 July 2004. The MIMI sensors observed frequent energetic particle activity in interplanetary space for several months before SOI. When the imaging sensor was switched to its energ…
The Evolution of Titan's Mid-Latitude Clouds
Sotin, C.; Langevin, Y.; Bellucci, G. +24 more
Spectra from Cassini's Visual and Infrared Mapping Spectrometer reveal that the horizontal structure, height, and optical depth of Titan's clouds are highly dynamic. Vigorous cloud centers are seen to rise from the middle to the upper troposphere within 30 minutes and dissipate within the next hour. Their development indicates that Titan's clouds …
Titan's Magnetic Field Signature During the First Cassini Encounter
Dougherty, Michele K.; Neubauer, Fritz M.; Russell, Christopher T. +8 more
The magnetic field signature obtained by Cassini during its first close encounter with Titan on 26 October 2004 is presented and explained in terms of an advanced model. Titan was inside the saturnian magnetosphere. A magnetic field minimum before closest approach marked Cassini's entry into the magnetic ionopause layer. Cassini then left the nort…
The Cassini UVIS Stellar Probe of the Titan Atmosphere
West, Robert A.; Esposito, Larry W.; Shemansky, Donald E. +3 more
The Cassini Ultraviolet Imaging Spectrometer (UVIS) observed the extinction of photons from two stars by the atmosphere of Titan during the Titan flyby. Six species were identified and measured: methane, acetylene, ethylene, ethane, diacetylene, and hydrogen cyanide. The observations cover altitudes from 450 to 1600 kilometers above the surface. A…
Cassini Imaging Science: Initial Results on Saturn's Atmosphere
Burns, J. A.; Neukum, G.; Wagner, R. +32 more
The Cassini Imaging Science Subsystem (ISS) began observing Saturn in early February 2004. From analysis of cloud motions through early October 2004, we report vertical wind shear in Saturn's equatorial jet and a maximum wind speed of ~375 meters per second, a value that differs from both Hubble Space Telescope and Voyager values. We also report a…
Ultraviolet Imaging Spectroscopy Shows an Active Saturnian System
West, Robert A.; Colwell, Joshua E.; Pryor, Wayne R. +13 more
Neutral oxygen in the saturnian system shows variability, and the total number of oxygen atoms peaks at 4 × 1034. Saturn's aurora brightens in response to solar-wind forcing, and the auroral spectrum resembles Jupiter's. Phoebe's surface shows variable water-ice content, and the data indicate it originated in the outer solar system. Sat…
Nightglow in the Upper Atmosphere of Mars and Implications for Atmospheric Transport
Bertaux, Jean-Loup; Leblanc, François; Perrier, Séverine +8 more
We detected light emissions in the nightside martian atmosphere with the SPICAM (spectroscopy for the investigation of the characteristics of the atmosphere of Mars) ultraviolet (UV) spectrometer on board the Mars Express. The UV spectrum of this nightglow is composed of hydrogen Lyman α emission (121.6 nanometers) and the γ and δ bands of nitric …
Deep Impact Observations by OSIRIS Onboard the Rosetta Spacecraft
Keller, Horst Uwe; Hviid, Stubbe F.; Lamy, Philippe +9 more
The OSIRIS cameras (optical, spectroscopic, and infrared remote imaging system) onboard the European Space Agency's Rosetta spacecraft observed comet 9P/Tempel 1 for 17 days continuously around the time of NASA's Deep Impact mission. The cyanide-to-water production ratio was slightly enhanced in the impact cloud, compared with that of normal comet…
A 5-Micron-Bright Spot on Titan: Evidence for Surface Diversity
Drossart, Pierre; Sotin, Christophe; Sicardy, Bruno +32 more
Observations from the Cassini Visual and Infrared Mapping Spectrometer show an anomalously bright spot on Titan located at 80°W and 20°S. This area is bright in reflected light at all observed wavelengths, but is most noticeable at 5 microns. The spot is associated with a surface albedo feature identified in images taken by the Cassini Imaging Sci…