Search Publications
Europa's ice-related atmosphere: The sputter contribution
Wurz, P.; Vorburger, A.
Europa, Jupiter's innermost icy satellite, is embedded well within Jupiter's magnetospheric plasma, an intense flux of ions and electrons that approximately co-rotate with Jupiter. The plasma can be thought of as consisting of two populations: The cold, thermal plasma containing charged particles with energies ranging from 1 eV to 1 keV, and the h…
Icy Saturnian satellites: Disk-integrated UV-IR characteristics and links to exogenic processes
Hendrix, Amanda R.; Filacchione, Gianrico; Schenk, Paul +2 more
Combined Cassini observations obtained at similar observing geometries in the ultraviolet through infrared spectral range, along with additional ultraviolet (UV) data from Hubble Space Telescope where available, are used to study system-wide trends in spectral albedos of the inner icy Saturnian satellites (Mimas, Enceladus, Tethys, Dione, Rhea). W…
Physical, spectral, and dynamical properties of asteroid (107) Camilla and its satellites
Kervella, P.; Berthier, J.; Carry, B. +24 more
The population of large 100+ km asteroids is thought to be primordial. As such, they are the most direct witnesses of the early history of our Solar System available. Those among them with satellites allow study of the mass, and hence density and internal structure. We study here the dynamical, physical, and spectral properties of the triple aster…
HST-STIS spectra and the redness of Saturn's rings
French, Richard G.; Cuzzi, Jeffrey N.; Hendrix, Amanda R. +3 more
We have observed the main rings of Saturn with the Space Telescope Imaging Spectrometer (STIS) on the Hubble Space Telescope (HST), covering the spectral region from 180-570 nm (including for the first time the critical near-UV range 190-340 nm) with very good signal to noise ratio and a radial resolution of approximately 160-330 km. After correct…
Dusk/dawn atmospheric asymmetries on tidally-locked satellites: O2 at Europa
Leblanc, François; Johnson, Robert E.; Oza, Apurva V.
We use a simple analytic model to examine the effect of the atmospheric source properties on the spatial distribution of a volatile in a surface-bounded atmosphere on a satellite that is tidally-locked to its planet. Spatial asymmetries in the O2 exosphere of Europa observed using the Hubble Space Telescope appear to reveal on average a…
A planetary-scale disturbance in a long living three vortex coupled system in Saturn's atmosphere
Hueso, R.; Sánchez-Lavega, A.; Rojas, J. F. +11 more
The zonal wind profile of Saturn has a unique structure at 60°N with a double-peaked jet that reaches maximum zonal velocities close to 100 ms-1. In this region, a singular group of vortices consisting of a cyclone surrounded by two anticyclones was active since 2012 until the time of this report. Our observation demonstrates that vorti…
Constraints on water vapor and sulfur dioxide at Ceres: Exploiting the sensitivity of the Hubble Space Telescope
Roth, Lorenz
Far-ultraviolet observations of dwarf-planet (1) Ceres were obtained on several occasions in 2015 and 2016 by the Cosmic Origins Spectrograph (COS) and the Space Telescope Imaging Spectrograph (STIS), both on board the Hubble Space Telescope (HST). We report a search for neutral gas emissions at hydrogen, oxygen and sulfur lines around Ceres from …
The New Horizons and Hubble Space Telescope search for rings, dust, and debris in the Pluto-Charon system
Hamilton, Douglas P.; Olkin, Cathy B.; Stern, S. Alan +11 more
We conducted an extensive search for dust or debris rings in the Pluto-Charon system before, during, and after the New Horizons encounter in July 2015. Methodologies included attempting to detect features by back-scattered light during the approach to Pluto (phase angle α ∼ 15°), in situ detection of impacting particles, a search for stellar occul…
Coloring Jupiter's clouds: Radiolysis of ammonium hydrosulfide (NH4SH)
Hudson, Reggie L.; Loeffler, Mark J.
Here we present our recent studies on the color and spectral reflectance changes induced by ∼0.9 MeV proton irradiation of ammonium hydrosulfide, NH4SH, a compound predicted to be an important tropospheric cloud component of Jupiter and other giant planets. Ultraviolet-visible spectroscopy was used to observe and identify reaction produ…
Composition and structure of fresh ammonia clouds on Jupiter based on quantitative analysis of Galileo/NIMS and New Horizons/LEISA spectra
Sromovsky, L. A.; Fry, P. M.
Ammonia gas has long been assumed to be the main source of condensables for the upper cloud layer on Jupiter, but distinctive spectral features associated with ammonia have been seen only rarely. Since both ammonia and NH4SH absorb in the 3 µm region, and widespread absorption in the 3 µm region was present (Sromovsky and Fr…