相关论文: Europa's Surface Water-ice Crystallinity and Corre…
Physical processing of Europan surface water ice by thermal relaxation, charged particle bombardment, and possible cryovolcanic activity can alter the percentage of the crystalline form of water ice compared to that of the amorphous form of…
The surface of Europa experiences a competition between thermally-induced crystallization and radiation-induced amorphization processes, leading to changes of its crystalline structure. The non-linear crystallization and…
Competing processes shape Europa's surface: geological activity replenishes material through resurfacing, while bombardment by charged particles alters surface chemical composition. Each process leaves distinct spectral signatures. We…
We present maps of surface composition of Europa's anti-jovian hemisphere acquired using high spatial resolution IFU multi-spectral data from the SPHERE instrument on the Very Large Telescope (0.95 to 1.65$\mu$m) and the NIMS instrument on…
Recent infrared observations at 1.5-4.0 $\mu m$ using large ground-based telescopes have suggested that Cl-bearing salts are likely present on Europa's surface as non-ice materials. The chemical compositions of those Cl-bearing salts are…
The Galileo Near Infrared Mapping Spectrometer (NIMS) collected spectra of Europa in the 0.7-5.2 $\mu$m wavelength region, which have been critical to improving our understanding of the surface composition of this moon. However, most of the…
The surface of Europa could contain the compositional imprint of a underlying interior ocean, but competing hypotheses differ over whether spectral observations from the Galileo spacecraft show the signature of ocean evaporates or simply…
Europa's interior is expected to be divided into the metallic core, rocky mantle and hydrosphere based on the moment of inertia factor estimated from gravity field measurements. Specifically, the thickness of the outermost water layer is…
We present best-fit values of porosity -- and the corresponding effective thermal inertiae -- determined from three different depths in Europa's near-subsurface (~1-20 cm). The porosity of the upper ~20 cm of Europa's subsurface varies…
Evidence for plumes of water on Europa has previously been found using the Hubble Space Telescope (HST) using two different observing techniques. Roth et al. (2014) found line emission from the dissociation products of water. Sparks et al.…
The icy surface of Europa is continuously bombarded by ions and electrons from Jupiter's magnetosphere. The bombardment of the particles dissociates water molecules on the surface of Europa and introduces impurities to the icy surface. Such…
The surface of Europa is geologically young and shows signs of current activity. Studying it from a photometric point of view gives us insight on its physical state. We used a collection of 57 images from Voyager's Imaging Science System…
Europa has been modified by a variety of geologic processes, exposing internally-derived materials that are heavily irradiated by charged particles trapped in Jupiter's magnetosphere. Prior spectral analysis of H2O ice on Europa relied on…
One of the clearest but unresolved questions for Europa is the thickness of its icy shell. Europa's surface is resplendent with geological features that bear on this question, and ultimately on its interior, geological history, and…
We study the evolution of the Vis-NIR reflectance spectrum of salty granular ice analog samples in a simulation chamber under conditions relevant to the surface of Europa. A novel application and custom calibration of a thermopile sensor…
Recent visible-wavelength observations of Europa's surface obtained with the Hubble Space Telescope revealed the presence of an absorption feature near 450 nm that appears spatially correlated with leading-hemisphere chaos terrain. This…
Images of Europa's surface taken by the Galileo Solid State Imager (SSI) show smooth features measuring a few kilometers, potentially resulting from eruptions of low-viscosity material such as liquid cryomagma. We estimated the volume of…
Europa's tenuous atmosphere results from sputtering of the surface. The trace element composition of its atmosphere is therefore related to the composition of Europa's surface. Magnesium salts are often invoked to explain Galileo Near…
Recent observations from the Hubble Space Telescope show a mid-UV absorption feature localized to leading hemisphere chaos regions on Europa. The same regions were previously found to have a visible absorption at 450 nm that was attributed…
The polarimetry of the light scattered by planetary surfaces is a powerful tool to provide constraints on their microstructure. To improve the interpretation of polarimetric data from icy surfaces, we have developed the POLarimeter for ICE…